Sensors incorporated into adhesive material

ABSTRACT

A disclosed apparatus includes sensors incorporated into adhesive material. In use, an apparatus may comprise an adhesive material and at least one split-ring resonator (SRR) disposed on or in the adhesive material. Additionally, the at least one SRR is formed from a carbon-containing material, and the adhesive material is a non-elastomeric material or a semi-rigid material. In some aspects, each SRR may resonate at a first frequency in response to an electromagnetic ping when the adhesive material is in a first state, and may resonate at a second frequency in response to the electromagnetic ping when the adhesive material is in a second state. A resonant frequency of the adhesive material may be based on physical characteristics of the adhesive material.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Patent application claims the benefit of priority to U.S.Provisional Patent Application No. 63/525,622, entitled “WATER DROPLETSENSING SYSTEMS AND METHODS” filed Jul. 7, 2023, U.S. Provisional PatentApplication No. 63/408,372, entitled “RESONANT SENSORS FOR ENVIRONMENTALHEALTH RISK DETECTION” filed Sep. 20, 2022, and U.S. Provisional PatentApplication No. 63/445,948, entitled “SENSORS INCORPORATED INTOSEMI-RIGID STRUCTURAL MEMBERS TO DETECT PHYSICAL CHARACTERISTIC CHANGES”filed Feb. 15, 2023, all of which are assigned to the assignee hereof;the disclosures of all prior Applications are considered part of and areincorporated by reference in this Patent Application.

This Patent Application is a continuation-in-part of and claims thebenefit of priority to U.S. patent application Ser. No. 17/940,256,entitled “SENSORS INCORPORATED INTO AIRBORNE VEHICLE COMPONENTS TODETECT PHYSICAL CHARACTERISTIC CHANGES” filed Sep. 8, 2022, which isassigned to the assignee hereof; the disclosures of which is consideredpart of and are incorporated by reference in this Patent Application.

U.S. patent application Ser. No. 17/940,256 claims the benefit ofpriority to: U.S. Provisional Patent Application No. 63/242,270,entitled “SENSORS INCORPORATED INTO SEMI-RIGID STRUCTURAL MEMBERS TODETECT PHYSICAL CHARACTERISTIC CHANGES” filed Sep. 9, 2021; U.S.Provisional Patent Application No. 63/247,680, entitled “SENSORSINCORPORATED INTO SEMI-RIGID STRUCTURAL MEMBERS TO DETECT PHYSICALCHARACTERISTIC CHANGES” and filed Sep. 23, 2021; U.S. Provisional PatentApplication No. 63/276,274, entitled “SENSORS INCORPORATED IN VEHICLECOMPONENTS TO DETECT PHYSICAL CHARACTERISTIC CHANGES, and filed Nov. 5,2021; and U.S. Provisional Patent Application No. 63/281,846, entitled“SENSORS INCORPORATED INTO AIRBORNE VEHICLE COMPONENTS TO DETECTPHYSICAL CHARACTERISTIC CHANGES” and filed Nov. 22, 2021, all of whichare assigned to the assignee hereof; the disclosures of all priorApplications are considered part of and are incorporated by reference inthis Patent Application.

U.S. patent application Ser. No. 17/940,256 is also acontinuation-in-part of and claims the benefit of priority to U.S.patent application Ser. No. 17/227,249, entitled “TUNED RADIO FREQUENCY(RF) RESONANT MATERIALS AND MATERIAL CONFIGURATIONS FOR SENSING IN AVEHICLE” and filed on Apr. 9, 2021, which in turn, claims the benefit ofpriority to U.S. Provisional Patent Application No. 63/008,262, entitled“RESONANCE SENSING IN TIRES” and filed on Apr. 10, 2020, and to U.S.Provisional Patent Application No. 63/036,796, entitled “RESONANCESENSING IN ELASTOMER-CONTAINING PRODUCTS” and filed on Jun. 9, 2020, allof which are assigned to the assignee hereof; the disclosures of allprior Applications are considered part of and are incorporated byreference in this Patent Application.

U.S. patent application Ser. No. 17/227,249 is also acontinuation-in-part of and claims the benefit of priority to U.S.patent application Ser. No. 16/829,355, entitled “TIRES CONTAININGRESONATING CARBON-BASED MICROSTRUCTURES” and filed on Mar. 25, 2020,which in turn, claims the benefit of priority to U.S. Provisional PatentApplication No. 62/985,550, entitled “RESONANT SERIAL NUMBER IN VEHICLETIRES” and filed on Mar. 5, 2020, to U.S. Provisional Patent ApplicationNo. 62/979,215, entitled “WASTE ENERGY HARVESTING AND POWERING INVEHICLES” and filed on Feb. 20, 2020, and to U.S. Provisional PatentApplication No. 62/824,440, entitled “TUNING RESONANT MATERIALS FORVEHICLE SENSING” and filed on Mar. 27, 2019, all of which are assignedto the assignee hereof; the disclosures of all prior Applications areconsidered part of and are incorporated by reference in this PatentApplication.

U.S. patent application Ser. No. 17/940,256 is a continuation-in-part ofand claims the benefit of priority to U.S. patent application Ser. No.17/340,493, entitled “SENSORS INCORPORATED INTO ELASTOMERIC MATERIALS TODETECT ENVIRONMENTALLY-CAUSED PHYSICAL CHARACTERISTIC CHANGES” and filedon Jun. 7, 2021, which in turn, claims the benefit of priority to U.S.Provisional Patent Application No. 63/036,118, entitled“CARBON-CONTAINING STICTION SENSORS” and filed on Jun. 8, 2020, to U.S.Provisional Patent Application No. 63/094,223, entitled “SENSORS FORELASTOMER PROPERTY CHANGE DETECTION” and filed on Oct. 20, 2020, and to,U.S. Provisional Patent Application No. 63/036,796, entitled “RESONANCESENSING IN ELASTOMER-CONTAINING PRODUCTS” and filed on Jun. 9, 2020, allof which are assigned to the assignee hereof; the disclosures of allprior Applications are considered part of and are incorporated byreference in this Patent Application.

U.S. patent application Ser. No. 17/340,493 is also acontinuation-in-part of and claims the benefit of priority to U.S.patent application Ser. No. 16/829,355, entitled “TIRES CONTAININGRESONATING CARBON-BASED MICROSTRUCTURES” and filed on Mar. 25, 2020,which in turn, claims the benefit of priority to U.S. Provisional PatentApplication No. 62/824,440, entitled “TUNING RESONANT MATERIALS FORVEHICLE SENSING” and filed on Mar. 27, 2019, all of which are assignedto the assignee hereof; the disclosures of all prior Applications areconsidered part of and are incorporated by reference in this PatentApplication.

TECHNICAL FIELD

This disclosure generally relates to sensors and, more specifically, toincorporating split ring resonators in or on structural members ofvehicles to detect changes properties of the structural members.

DESCRIPTION OF RELATED ART

Despite advances in automotive automation, defogging windshields remainsa persistent issue for most humans in wetter climates. Additionally,water droplets pose a significant issue not only for drivers but alsofor safety of aircraft, where accumulation of water droplets may formice particles, which in turn may damage or comprise the integrity of theaircraft. As such, there is thus a need for addressing these and/orother issues associated with the prior art.

SUMMARY

This Summary is provided to introduce in a simplified form a selectionof concepts that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tolimit the scope of the claimed subject matter.

A disclosed apparatus includes sensors incorporated into adhesivematerial. In use, an apparatus may comprise an adhesive material and atleast one split-ring resonator (SRR) disposed on or in the adhesivematerial. Additionally, the at least one SRR is formed from acarbon-containing material, and the adhesive material is anon-elastomeric material or a semi-rigid material. In some aspects, eachSRR may resonate at a first frequency in response to an electromagneticping when the adhesive material is in a first state, and may resonate ata second frequency in response to the electromagnetic ping when theadhesive material is in a second state. A resonant frequency of theadhesive material may be based on physical characteristics of theadhesive material.

A disclosed water droplet sensing system and methods using split-ringresonators, which may be embedded within a material. In use, a componentincludes at least one split-ring resonator (SRR) which may be embeddedwithin a material of the component. The at least one SRR may be formedfrom a composite material. Additionally the at least one SRR may beconfigured to form a signal that is correlated with a concentration ofwater proximate to the at least one SRR. In some aspects, each SRR mayresonate at a first frequency in response to an electromagnetic pingwhen the material is in a first state, and may resonate at a secondfrequency in response to the electromagnetic ping when the material isin a second state. A resonant frequency of the material may be based onphysical characteristics of the material (including fluid accumulationon the material).

In various implementations, an electromagnetic state sensing device(EMSSD) may include split-ring resonators (split ring resonators)configured to be embedded within a material. Each split ring resonatormay be formed from a three-dimensional (3D) monolithic carbonaceousgrowth and respond to an electromagnetic stimulus signal emitted from auser device (e.g., a smartphone, a radio frequency identification (RFID)reader, or a near-field communication (NFC) device) to generate anelectromagnetic return signal in response to the electromagneticstimulus signal. The electromagnetic return signal may indicate a stateof the material in a position proximate to a respective split ringresonator. The split ring resonator may resonate at a first frequency inresponse to the electromagnetic stimulus signal when the material is ina first state and may resonate at a second frequency in response to theelectromagnetic stimulus signal when the material is in a second state.A natural resonant frequency of the 3D monolithic carbonaceous growthmay be based on physical characteristics of the material, e.g.,permittivity and/or permeability. In this way, an extent of shift of anatural resonance frequency in response to the electromagnetic stimulussignal of the first split ring resonator and the second split ringresonator may be indicative of an amount of deformation of the material.

In various implementations, each split ring resonator may indicate afirst condition of the material by generating a first electromagneticreturn signal in response to the electromagnetic stimulus signal, andmay indicate a second condition of the material by generating a secondelectromagnetic return signal in response to the electromagnetic ping.In addition, the first electromagnetic return signal may have a firstfrequency, and the second electromagnetic return signal may have asecond frequency different than the first frequency.

The state of the material may include a deformation of the material. Insome aspects, the split ring resonator may indicate deformation of thematerial by generating a first electromagnetic return signal in responseto the electromagnetic stimulus signal, and may indicate a lack ofdeformation of the material by generating a second electromagneticreturn signal in response to the electromagnetic ping.

In some implementations, at least one split ring resonator includes aresonance portion, which may resonate at a first frequency in responseto the electromagnetic stimulus signal when the state of the materialexceeds a threshold, and may resonate at a second frequency in responseto the electromagnetic stimulus signal when the state of the material isbeneath the threshold. Some of the split ring resonators may each have afirst split-ring resonator (split ring resonator) with first carbonparticles that may uniquely resonate in response to an electromagneticstimulus signal based on a concentration level of the first carbonparticles within the first split ring resonator. Some split ringresonators may have a second split ring resonator adjacent to the firstsplit ring resonator with second carbon particles that may uniquelyresonate in response to the electromagnetic stimulus signal based atleast in part on a concentration level of the second carbon particleswithin the second split ring resonator.

Each of the first carbon particles and second carbon particles may bechemically bonded with the material. In some aspects, first carbonparticles may include first aggregates forming a first porous structure,and the second carbon particles may include second aggregates forming asecond porous structure. In this way, an amplitude of resonance of thefirst split ring resonator or the second split ring resonator may beindicative of an extent of wear of the material. In addition, the firstsplit ring resonator may resonate at a first frequency in response tothe electromagnetic ping, and the second split ring resonator mayresonate at a second frequency in response to an electromagnetic ping,where the first frequency is different than the second frequency. Eachof the first split ring resonator and the second split ring resonatormay each have an attenuation point associated with a frequency responseto the electromagnetic ping.

In some implementations, split ring resonators are disposed instructural members of an EVTOL. Further, techniques are disclosed toshow how resonant sensors play a significant role in the safety andmaneuverability of EVTOL vehicles as well as pertaining to the safetyand maneuverability of other types of airborne vehicles.

In one implementation, an airborne vehicle component may comprise atleast one split-ring resonator (SRR) embedded within a material that maycomprise at least a portion of the airborne vehicle component.Additionally, the at least one SRR may be formed from athree-dimensional (3D) monolithic carbonaceous growth and the at leastone SRR may be configured to respond to an electromagnetic stimulusemitted from an antenna. Further, the at least one SRR, in combinationwith the material of the airborne vehicle component that is proximate tothe at least one SRR, may modulate the electromagnetic stimulus to forman electromagnetic return signal that may indicate a state of thematerial at the position proximate to the at least one SRR. In oneembodiment, a location of the material may be at a position proximate to(or near) the at least one SRR.

In various embodiments, the airborne vehicle may be one of: a verticaltake-off and landing (VTOL) aircraft, an electric vertical take-off andlanding (eVTOL) aircraft, a drone, a passenger drone, a commercialaircraft, a military aircraft, or a rocket. Additionally, the at leastone SRR may be used to locate a position of the airborne vehicle withrespect to a landing pad. For example, at least three SRRs of the atleast one SRR may be used to triangulate a position of the airbornevehicle component.

The material may be found on at least one of: a propeller blade, a bodymaterial, landing gear, a cockpit interface, or a structural component.Additionally, the state of the material may indicate at least one ofsurface flexion, propeller flexion, or landing gear flexion. The stateof the material may also be correlated to indicate at least one ofpressure, location, temperature, or elevation.

In some implementations, the at least one SRR may be configured toresonate at a first frequency in response to the electromagneticstimulus when the material is in a first state, and may be configured toresonate at a second frequency in response to the electromagneticstimulus when the material is in a second state. Additionally, a tunedresonant frequency of the 3D monolithic carbonaceous growth may be basedat least in part on one or more physical characteristics of thematerial.

In various embodiments, the at least one SRR may be configured toindicate a first condition of the material by generating a firstelectromagnetic return signal in response to the electromagneticstimulus, and may be configured to indicate a second condition of thematerial by generating a second electromagnetic return signal inresponse to the electromagnetic stimulus. Additionally, the firstelectromagnetic return signal has a first frequency, and the secondelectromagnetic return signal has a second frequency different than thefirst frequency. Further, the state of the material may include adeformation of the material, and/or the at least one SRR may beconfigured to indicate the deformation of the material by generating afirst electromagnetic return signal in response to the electromagneticstimulus, and may be configured to indicate a lack of deformation of thematerial by generating a second electromagnetic return signal inresponse to the electromagnetic stimulus. A resonant frequency of 3Dmonolithic carbonaceous growth may be based at least in part on eitheror both of a permittivity and a permeability of the material.

In one embodiment, one or more SRRs may further comprise a firstsplit-ring resonator (SRR) including a plurality of first carbonparticles configured to uniquely resonate in response to theelectromagnetic stimulus based at least in part on a concentration levelof the first carbon particles within the first SRR. Additionally, theone or more SRRs may further comprise a second SRR and include aplurality of second carbon particles configured to uniquely resonate inresponse to the electromagnetic stimulus based at least in part on aconcentration level of the second carbon particles within the secondSRR. Further, each of the first carbon particles and second carbonparticles may be chemically bonded with the material, the first carbonparticles may include first aggregates forming a first porous structure,and/or the second carbon particles may include second aggregates forminga second porous structure.

Still yet, in other an amplitude of resonance of at least one of thefirst SRR or the second SRR may be indicative of an extent of wear ofthe material. Additionally, the first SRR may be configured to resonateat a first frequency in response to the electromagnetic stimulus, andthe second SRR may be configured to resonate at a second frequency inresponse to the electromagnetic stimulus, the first frequency may bedifferent than the second frequency, an extent of shift of a naturalresonance frequency in response to the electromagnetic stimulus of thefirst SRR and the second SRR may be indicative of an amount ofdeformation of the material, each of the first SRR and the second SRRmay have an attenuation point, and/or the attenuation point of each thefirst SRR and the second SRR may be associated with a frequency responseto the electromagnetic stimulus.

In one implementation, a landing pad may comprise at least onesplit-ring resonator (SRR) configured to be embedded within a materialthat may comprise at least a portion of the landing pad. Additionally,the at least one SRR may be formed from a three-dimensional (3D)monolithic carbonaceous growth and the at least one SRR may beconfigured to respond to an electromagnetic stimulus emitted from anantenna. Further, the at least one SRR, in combination with the materialof the landing pad and its environment, may modulate the electromagneticstimulus to form an electromagnetic return signal that may indicate atleast one environmental condition at the position proximate to the atleast one SRR.

Details of one or more implementations of the subject matter describedin this disclosure are set forth in the accompanying drawings and thedescription below. Other features, aspects, and advantages will becomeapparent from the description, the drawings, and the claims. Note thatthe relative dimensions of the following figures may not be drawn toscale.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 presents an in-situ vehicle control system including varioussensors formed of carbon-containing composites tuned to demonstratedesirable radio frequency (RF) signal resonance and response upon beingpinged, in accordance with one embodiment.

FIG. 2 depicts a signal processing system that analyzes emitted and/orreturned RF signals that are frequency-shifted and/or attenuated bysensors formed of carbon-containing tuned RF resonance materials, inaccordance with one embodiment.

FIG. 3 illustrates a signature classification system, in accordance withone embodiment.

FIG. 4 depicts a series of tire condition parameters that are sensedfrom changes in RF resonance of various layers of carbon-containingtuned RF resonance materials, in accordance with one embodiment.

FIG. 5 depicts a schematic diagram of an apparatus used for tuningmultiple plies of a tire by selecting carbon-containing tuned RFresonance materials from separate and independent reactors forincorporation into the body of a single tire assembly, in accordancewith one embodiment.

FIGS. 6 and 7 depict sets of example condition signatures that may beemitted from new tires formed of layers of carbon-containing tuned RFresonance materials, in accordance with one embodiment.

FIG. 8 depicts a top-down schematic view of an example split-ringresonator (split ring resonator) configuration including two concentricsplit ring resonators, in accordance with one embodiment.

FIG. 9 depicts a schematic diagram showing a complete tire diagnosticssystem and apparatus for tire wear sensing through impedance-basedspectroscopy, in accordance with one embodiment.

FIGS. 10 and 11 depict schematic diagrams relating to tire informationtransferred via telemetry into a navigation system, as well as equipmentfor manufacturing printed carbon-based materials, in accordance with oneembodiment.

FIG. 12 depicts a schematic diagram for resonant serial number-baseddigital encoding of vehicle tires through tire tread layer and/or tirebody ply-print encoding, in accordance with one embodiment.

FIG. 13 illustrates resonance mechanisms that contribute to the ensemblephenomenon arising from different proximally-present resonator types, inaccordance with one embodiment.

FIG. 14 is an example temperature sensor including one or more of thepresently disclosed split ring resonators, in accordance with oneembodiment.

FIG. 15 is a graph of measured resonant signature signal intensity (indecibels, dB) relative to height (in millimeters, mm) of tire treadlayer loss, in accordance with one embodiment.

FIG. 16 is a graph of measured resonant signature signal intensity (indecibels, dB) relative to the natural resonance frequency of split ringresonators showing resonance response shift proportionate to tire plydeformation, in accordance with one embodiment.

FIG. 17 is a graph of signal intensity relative to chirp signalfrequency for split ring resonators that may resonate corresponding toan encoded serial number, in accordance with one embodiment.

FIG. 18A through FIG. 18Y depict carbonaceous materials used as aformative material to produce any of the presently disclosed resonators(e.g., split ring resonators), in accordance with one embodiment.

FIGS. 19A1 and 19A2 provide a depiction of a split ring resonator, orplurality of split ring resonators, being placed in concrete before theconcrete is to be poured into a given structural form, in accordancewith one embodiment.

FIGS. 19B1 and 19B2 show a depiction of columns containing the splitring resonator, or plurality of split ring resonators, and an equationfor measuring the change within the structural members, in accordancewith one embodiment.

FIG. 20 illustrates the utilization of split ring resonators externallyon structural members varying in shapes that already in use. FIG. 20also displays examples of possible factors and equations that may bevital in determining the size, orientation, location, and application ofthe split ring resonator or split ring resonators on the structuralmember, in accordance with one embodiment.

FIG. 21 is a flow chart representing the process in which the split ringresonator is implemented in the given applications, in accordance withone embodiment.

FIG. 22A1 through 22A3 are being presented to illustrate use of splitring resonators or a plurality of split ring resonators within roadsidebarriers, in accordance with one embodiment.

FIG. 22B depicts a roadside barrier used in a racetrack showingstructural components that constitute the roadside barrier in which asplit ring resonator or split ring resonators can be placed, inaccordance with one embodiment.

FIG. 23 shows a depiction of split ring resonators disposed on thesurface of a concrete structure after the concrete has been poured intoa given structural form, in accordance with one embodiment.

FIG. 24A depicts a sensing laminate including alternating layers ofcarbon-containing resin and carbon fiber in contact with one-another, inaccordance with one embodiment.

FIGS. 24B1 and 24B2 depict a frequency-shifting phenomenon asdemonstrated by a sensing laminate including carbon-containing tuned RFresonance materials, in accordance with one embodiment.

FIG. 24B3 is a graph depicting idealized changes in RF resonance as afunction of deflection, in accordance with one embodiment.

FIG. 24B4 is a graph depicting changes in RF resonance for 4-layer and5-layer laminates, in accordance with one embodiment.

FIG. 24C depicts surface sensor deployments in areas of a vehicle, inaccordance with one embodiment.

FIG. 25A provides a depiction of interaction between a vehicle and splitring resonators disposed in roadway asphalt and/or on the surface of aroad, in accordance with one embodiment.

FIG. 25B provides a depiction of how split ring resonators disposedwithin or on a tire can be used to measure tire stiction, in accordancewith one embodiment.

FIG. 26 depicts placement of split ring resonators disposed in roadwayasphalt and/or on the surface of a road, in accordance with oneembodiment.

FIG. 27 is a flow chart representing the process to determine tirestiction, in accordance with one embodiment.

FIG. 28 shows a correlation between measured frequencies and treadthickness, in accordance with one embodiment.

FIG. 29 shows a section of a vehicle surface where an array ofindividually configured split ring resonators are disposed, inaccordance with one embodiment.

FIG. 30 depicts a configuration of the split ring resonators in afrequency bin, in accordance with one embodiment.

FIG. 31 shows a chart of detection of time-based variation ofdeflection, as indicated by time-based variation of the resonantfrequency, in accordance with one embodiment.

FIG. 32 depicts a signature classification system that processes signalsreceived from sensors formed of carbon-containing tuned resonancematerials, in accordance with one embodiment.

FIG. 33 shows a depiction of split ring resonators disposed in and/or ona drone, and/or a drone platform, in accordance with one embodiment.

FIG. 34 shows a depiction of split ring resonators disposed in and/or onan aerial vehicle, in accordance with one embodiment.

FIG. 35 shows a depiction of split ring resonators disposed in and/or onan aerial vehicle, as well as landing location sensors, in accordancewith one embodiment.

FIGS. 36A and 36B show two depictions of split ring resonators disposedin and/or on aircraft, in accordance with one embodiment.

FIG. 37A shows a depiction of split ring resonators disposed in and/oron a rocket, in accordance with one embodiment.

FIG. 37B shows a depiction of split ring resonators disposed in and/oron a rocket, and/or a landing platform, as well as landing locationsensors, in accordance with one embodiment.

FIG. 38A is a flow chart relating to reporting feedback from split ringresonators, in accordance with one embodiment.

FIG. 38B is a flow chart relating to landing an aerial vehicle and/ordrone using split ring resonators, in accordance with one embodiment.

FIG. 39 shows a depiction of meta-materials in a dielectric matrix, andcircuitry relating thereto, in accordance with one embodiment.

FIG. 40 shows a depiction of a split ring resonator embedded within anopen or closed cell material, in accordance with one embodiment.

FIG. 41 shows a depiction of pressure sensors using open or closed cellmaterial, in accordance with one embodiment.

FIG. 42 shows a depiction of wind pressure sensing data using open orclosed cell material, in accordance with one embodiment.

FIG. 43 shows a depiction of a path and circuitry relating to frequencyselective conductivity, in accordance with one embodiment.

FIG. 44 shows a depiction of many industries in which the use of splitring resonators may be applicable, in accordance with one embodiment.

FIG. 45 shows a water droplet sensing vehicle application, in accordancewith one embodiment.

FIG. 46 shows a method for remedying sensed water droplets, inaccordance with one embodiment.

FIG. 47 shows a water droplet sensing aircraft application, inaccordance with one embodiment.

FIG. 48 shows a leaky antenna interrogation system for water dropletsensing, in accordance with one embodiment.

FIG. 49 shows an architecture for leaky feeder antenna, in accordancewith one embodiment.

FIGS. 50A and 50B show sensors integrated into an adhesive, inaccordance with one embodiment.

Like reference numbers and designations in the various drawings indicatelike elements.

DETAILED DESCRIPTION

Various implementations of the subject matter disclosed herein relategenerally to deploying durable sensors (e.g., split-ring resonators,split ring resonators), made from carbonaceous microstructures. Thesensors may be incorporated within vehicle components, e.g., within theplies of the body of a conventional, currently commercially availablepneumatic (referring to air, nitrogen or other gas-filled) tire,next-generation airless solid tires, as well as in other positions,e.g., within vehicle bodywork. The sensors may be embedded withinportions of tire plies and/or tire tread, e.g., rubber in contact withpavement or ground. Routine tire usage results in degradation of contactsurfaces, eventually resulting in bald (treadles) tires incapable ofadequately adhering to road surfaces, especially in inclement weatherconditions, e.g., snow, heavy rain, etc. Deterioration of tire pliescontaining sensors produces corresponding detectable changes in sensorresponse behavior, e.g., relative to both forward rotation and tirestrain encountered in lateral tire sliding, e.g., “drifting,” a commonmaneuver in some enthusiast communities. In this way, both routine(e.g., forward-rotation) tire deterioration can be detected by changesin expected sensor resonance response behavior and loss of tire stiction(e.g., during drift maneuvers) by observing shifts in expected sensorresonance response behavior (e.g., as accomplished through frequencyshift-keying, a concept explained further below). Stiction, as commonlyunderstood, may imply the static friction that needs to be overcome toenable relative motion of stationary objects in contact, e.g., as may beencountered during performance driving maneuvers involving lateralmovement, such as drifting. This is comparison to kinetic and/or dynamicfriction, which may imply concurrent movement between both contactingsurfaces, etc.

It is to be appreciated that, as described herein, the sensors may alsobe incorporated as well within building materials, constructionmaterials, metallic materials, polymers, plastics, foams (both open andclosed cell), etc. Further, application of such materials may be withinindustries beyond the automobile (e.g. aerospace, construction, mining,etc.).

The carbonaceous materials can be tuned during synthesis to achievespecific expected radio frequency (RF) signal shift (referring tofrequency shift) and signal attenuation (referring to the diminishmentof signal magnitude) behavior relative to RF signals emitted. Equipmentcapable of emitting the RF signals may include, for example, atransceiver mounted within one or wheel wells of a vehicle equipped withthe disclosed systems and/or by an inductor-capacitor (LC) circuit, alsoreferred to (interchangeably) as a tank circuit, LC circuit orresonator. The presently disclosed implementations do not require movingparts and are thereby less susceptible to wear and tear resultant ofroutine road usage. Split ring resonators function with pre-existingvehicle electronic components, aerial vehicle electronic components,construction (including concrete) components, etc. Target RF resonancefrequency values of disclosed ingredient carbonaceous materials may betuned within a reaction chamber or a reactor to demonstrate interactionto yield target performance characteristics. The characteristics may befor any number of applications, e.g., knobby, low-pressure off-roadtires as well as race-track only slicks without tread. Split ringresonators formed of unique carbonaceous materials demonstrate frequencyshifting and/or signal attenuation at specified radio frequencies (RF),e.g., 0.01 GHz to 100 GHz, which may be tuned pursuant to desiredapplications. Regarding tunability, the carbonaceous materials may beinnately grown (e.g., self-nucleated) in a reactor from acarbon-containing gaseous species without requiring a seed particle togenerate ornate 3D structures.

Changes in the environment (e.g., snow, rain, etc.) surrounding avehicle equipped with the disclosed materials and systems may affect theresonance, frequency shifting, and/or signal attenuation behavior of thesplit ring resonators. As a result, even minute tire condition changescan be detected and communicated to the driver. For example, should atire ply containing one or more split ring resonators contact a roadsurface (e.g., forward-rotation) and thereby deteriorate and/or deformover time, resonance of that split ring resonator within thedeteriorating and/or deforming tire ply may change. Further, otherdetectable changes may occur during drifting (e.g., sideways movement)scenarios, such that signal response of the affected tire ply and/ortread layer containing the split ring resonator may indicate thepresence or absence of that tread layer, as well as the degree of wear.As a result, split ring resonators may accurately and precisely detectboth abrupt or gradual transitions in weather or other environmentalconditions (e.g., performance driving maneuvers).

Detectable changes and/or shifts in in RF range resonant frequencyresponse of split ring resonators may be detected by stimulating the RFresonant materials within each split ring resonator with anelectromagnetic (EM) signal having a known frequency. In someconfigurations, EM signals may be initially output by an antennae (alsomounted on the vehicle) and/or further propagated by patterned resonantcircuits (referred to herein as “resonators”, which can be 3D printedonto the tire body plies) mounted within one or more wheel wells. Inthis way, attenuation and/or frequency shifts associated with respectivesplit ring resonators relative to the emitted signal may beelectronically observed and analyzed to gauge current environmentalconditions. In addition, changes in the RF resonant frequency (orfrequencies) may be observed and compared to known and discretecalibration points to determine tire air pressure as measured at one ormore defined detection points on the vehicle's bodywork at a givenmoment in time.

Conventional use of tires, such as that encountered during on-roaddriving for most road tires, or off- for off-road tires, can causeslight deformations of portions of the tire, which can cause a change inthe natural RF resonance frequency of a respective split ring resonator(at the time y being ‘pinged’ by a RF signal). Such changes in thenatural resonance frequencies (as associated with presently disclosedcarbons forming various split ring resonators) can be detected andcompared to known calibration points to determine conditions inside thetire. Systems employing antennae in combination with the presentlydisclosed split ring resonators incorporated within tire plies mayaccommodate both the sensing of tire ply property changes andreporting-out to associated telemetry equipment in the vehicle.

Of course, it is to be appreciated that although the application ofsplit ring resonators is described in detail with respect to tires (andthe automotive industry), such application may equally apply to otherindustries (e.g. aerospace, construction, materials, mining, oil,concrete, etc.).

Presently disclosed split ring resonators may be tuned to detect evenminute changes in physical properties of respective tire plies (and/orany material or substance in which the split ring resonators areembedded in or on), including changes due to air pressure on a vehicleskin, or due to any external application of forces in/on a tire. Suchchanges can be detected by “pinging” (e.g., emitting, and laterobservation and analysis of RF signals) for then processing the uniqueset of detected properties (e.g., the “signature”) of a given tire ply,tread layer, or other surface or region as demonstrated by, for example,frequency domain return. Various mechanisms for calibrating an observedsignal signature and processing a return signature are discussed.Methods for fabrication of a tire with passive embedded sensors in theform of tuned carbon structures that interact with the elastomer aredisclosed. For example, mechanisms used for making a tire from multipleplies may influence split ring resonator natural resonance frequencybehavior. In addition, tires may be constructed including multiple tireplies, each tire ply incorporating a distinct tuned carbon having aunique tuned carbonaceous microstructure, which may be micron-sized, oralternatively in any one or more of the nanometer, micro, evenmeso-particle sizes up to the millimeter (mm) level.

Disclosed split ring resonators may permit for self-powered signaturesfrom resonance in the GHz and MHz range as made possible by tribologicalpower generators (e.g., generating electric current upon, for example,rotation of a vehicle tire and its repeated friction and/or contact withthe pavement or ground). Such tribological components can be integratedor otherwise incorporated within multiple steel belts in betweenelastomer layers in one or more vehicle tire plies. In this way, thesplit ring resonators may be charged (and/or powered) by thetriboelectric generator for the resonator to resonate (and thus emit RFsignals) and discharge. The resonator can be configured to accommodaterepeated charge-discharge cycles and be in any one or more of a varietyof shapes and/or patterns, including ovals that have an inherentresonant value or properties (based on its formative materials and/orconstruction).

Changes in the shape or orientation of the resonator may result in acorresponding change of any associated resonation constants. As aresult, any change in tire physical properties due to deformation (orany similar deformation of the material in which or on which the splitring resonators are found), e.g., under static conditions like internaltire pressure, or under dynamic conditions such as those encounteredwhile running over Bots Dots, can change the shape or orientation of arespective split ring resonator. Different resonator patterns (e.g., inaddition, or the alternative, to split ring resonators) can be used torespond with greater sensitivity to one type of deformation over another(such as referring to lateral deformation encountered while movingaround a curve compared to vertical motion encountered while runningover gravel or a rough surface). In addition to configurations wheresplit ring resonators change in signal response behavior based on tiredeformation, split ring resonators may also electronically communicatewith other signal attenuation detection capabilities, e.g., asassociated with a digital signal processing, DSP, computer chip and/ortransducers placed within the wheel well, or even within the rim, of awheel. DSP may function with external transceiver (a semiconductor chip)for both stimulus and response; while option. Split ring resonators mayalso communicate with tribological generators incorporated in individualtire plies and demonstrate resonance behavior that can detected by anexternal receiver.

As found through the detailed description, illustrative informationpresented is intended to set forth various architectures (includingthose optional) and uses. It should be strongly noted that theinformation is set forth for illustrative purposes (to provide asthorough a description as possible) and should not be construed aslimiting in any manner. Any of the following features may be optionallyincorporated with or without the exclusion of other features described.

FIG. 1 is a schematic diagram a vehicle condition detection system 100e.g., intended to be equipped onto a vehicle such as an automobileand/or truck. The vehicle condition detection system 100 may includesensors, such as tuned RF resonance components 108 (e.g., split-ringresonators, such as that shown in FIG. 8 ). Each of the as tuned RFresonance components 108 may be formed from multiple carbon-basedmicrostructural materials, aggregates, agglomerations, and/or the likesuch as those disclosed by Stowell, et al., in U.S. patent applicationSer. No. 16/785,020 entitled “3D Self-Assembled Multi-Modal Carbon-BasedParticle” filed on Feb. 7, 2020 (referred to collectively as“carbonaceous materials”), the disclosure of which is incorporated byreference for all purposes. The tuned RF resonance components 108 can beincorporated into any one or more of belt sensors 104, hose sensors 105,tire sensors 106, and transceiver antennas 102 on a vehicle, such as aconventional driver-driven automobile or a fully-autonomous transportpod or vehicle capable of operating to move vehicle occupants without ahuman driver.

The tuned RF resonance components 108 can be configured toelectronically and/or wirelessly communicate, such as by measurement ofsignal frequency shift or attenuation, with any one or more of atransceiver 114, a vehicle central processing unit 116, a vehicle sensordata receiving unit 118, a vehicle actuators control unit 120, andactuators 122 including doors, windows, locks (collectively 124), enginecontrols 126, navigation/heads-up displays 128, suspension control 129,and an airfoil trim 130. The tuned RF resonance components 108 can causea shift in observed frequencies of emitted RF signals (referred to as a“frequency-shift”, implying any change in frequency) via emitted RFsignals 110 and/or returned RF signals 112 with the transceiver 114.Reference to the returned RF signals 112 corresponding to emitted RFsignals 110 may refer to the electronic detection of frequency shift orattenuation of the emitted RF signals 110 relative to one or more of thetuned RF resonance components 108 integrated into any one or more of thebelt sensors 104, the hose sensors 105, the tire sensors 106, thetransceiver antennas 102 on a vehicle, and/or the like (e.g., ratherthan an actual physical reflection or return of a signal from a sensor).The emitted RF signals 110 and the returned RF signals 112 can be incommunication with (and therefore also assessed by) any one or more ofthe vehicle central processing unit 116, the vehicle sensor datareceiving unit 118, the vehicle actuators control unit 120, and/or theactuators 122. The vehicle condition detection system 100 can beimplemented using any suitable combination of software and hardware.

Any one or more of the depicted various sensors of the vehicle conditiondetection system 100 can be formed of carbon-based microstructures tunedto achieve a specific RF resonance behavior upon being “pinged”(referring to being hit or otherwise contacted by) emitted RF signals.The vehicle condition detection system 100 (or any aspect thereof) canbe configured to be implemented in any conceivable vehicle useapplication, area, or environment, such as during inclement weatherconditions including sleet, hail, snow, ice, frost, mud, sand, debris,uneven terrain, water and/or the like.

The tuned RF resonance components 108 can be disposed around and/or onthe vehicle (such as within the cabin, engine compartment, or the trunk,or on the body of the vehicle). As shown in FIG. 1 , the tuned RFresonance components can include belt sensors 104, hose sensors 105,tire sensors 106, and transceiver antennas 102, any one or more of whichcan be implemented in modern vehicles during their production, or(alternatively) retro-fitted to pre-existing vehicles, regardless oftheir age and/or condition. The tuned RF resonance components 108 can beformed, in part, using readily available materials such as fiberglass(such as, for airfoils) or rubber (such as, for tires) or glass (suchas, for windshields). These conventional materials can be combined withcarbon-based materials, growths, agglomerates, aggregates, sheets,particles and/or the like, such as those self-nucleated in-flight in areaction chamber or reactor from a carbon-containing gaseous species andformulated to: (1) improve the mechanical (such as tensile, compressive,shear, strain, deformation and/or the like) strength of a compositematerial in which they are incorporated; and/or, (2) to resonate at aparticular frequency or set of frequencies (within the range of 10 GHzto 100 GHz). Variables that dominate RF resonance properties andbehavior of a material can be controlled independently from thevariables responsible for control of material strength.

Radio Frequency (RF) based stimulation (such as that emitted by thetransceiver 114 or emitted by a resonator) can be used to emit RFsignals to the tuned RF resonance components 108, the actuators 122(and/or the like, such as sensors implemented in or on the tuned RFresonance components 108) to detect their respective resonance frequencyor frequencies, as well as frequency shifts and patterns observed in theattenuation of emitted signals (which may be affected by internal orexternal conditions). For example, if a tuned RF resonance component(such as the tire sensors 106) has been specially prepared (referred toas being “tuned”) to resonate at a frequency of approximately 3 GHz,then the tire sensors 106 can emit sympathetic resonance or sympatheticvibrations (referring to a harmonic phenomenon wherein a formerlypassive string or vibratory body responds to external vibrations towhich it has a harmonic likeness) when stimulated by a 3 GHz RF signal.

These sympathetic vibrations can occur at the stimulated frequency aswell in overtones or sidelobes deriving from the fundamental 3 GHz tone.If a tuned resonance component (of the tuned RF resonance components108) has been tuned to resonate at 2 GHz, then when the tuned resonancecomponent is stimulated by a 2 GHz RF signal, that tuned resonancecomponent will emit sympathetic vibrations as so described. Thesesympathetic vibrations will occur at the stimulated frequency as well asin overtones or sidelobes (in engineering, referring to local maxima ofthe far field radiation pattern of an antenna or other radiation source,that are not the main lobe) deriving from the fundamental 2 GHz tone.Many additional tuned resonance components can be situated proximally toan RF emitter. An RF emitter might be controlled to first emit a 2 GHzping, followed by a 3 GHz ping, followed by a 4 GHz ping, and so on.This succession of pings at different and increasing frequencies may bereferred to as a “chirp”.

Adjacent tire plies (such as those in contact with each other) within atire body, such as that generally shown by FIGS. 5-7 , can have varyingconcentration levels or configurations of carbon-based microstructuresto define sensors incorporated within that (referring to the respective)tire body ply and/or tread layer to resonate at varying distinctfrequencies that are not harmonic with one-another. That is,non-harmonic plies can ensure a distinct and easily recognizabledetection of a particular tire body ply and/or tread layer (or othersurface or material) relative to others with minimal risk of confusiondue to signal interference caused by (or otherwise associated with)harmonics.

The transceiver 114 (and/or a resonator, not shown in FIG. 1 ) can beconfigured to transmit the emitted RF signals 110 to any one or more ofthe tuned RF resonance components 108 to digitally recognize frequencyshift and/or attenuation of the returned RF signals 112 from any one ormore of the tuned RF resonance components 108. Such “returned” signals112 can be processed into digital information that can be electronicallycommunicated to a vehicle central processing unit 116, that interactswith a vehicle sensor data receiving unit 118 and/or a vehicle actuatorscontrol unit 120, which send further vehicle performance related signalsbased on sensor data received. The returned signals 112 can at leastpartially control the actuators 122. That is, the vehicle actuatorscontrol unit 120 can control the actuators 122 to operate any one ormore of the doors, windows, locks 124, the engine controls 126, thenavigation/heads-up displays 128, the suspension control 129, and/or theairfoil trim 130 according to feedback received from the vehicle sensordata receiving unit 118 regarding vehicle component wear or degradationas indicated by the tuned RF components in communication with thetransceiver 114.

Detection of road debris and inclement weather conditions uponmonitoring behavior (such as frequency shift and/or attenuation) of thereturned RF signals 111 can, for example, result in the actuators 122triggering a corresponding change in the suspension control 129. Suchchanges can, for example, include softening suspension settings toaccommodate driving over the road debris, while later tighteningsuspension settings to accommodate enhanced vehicle responsiveness asmay be necessary to travel during heavy rain (and thus low traction)conditions. The variations of such control by the vehicle actuatorscontrol unit 120 are many, where any conceivable condition exterior tothe vehicle can be detected by the transceiver (as demonstrated byfrequency shifting and/or attenuation of the emitted RF signals 110and/or the returned RF signals 112).

Any of the tuned RF resonance components 108 forming the describedsensors can be tuned to resonate when stimulated at particularfrequencies, where a defined shift in frequency or frequencies (ascaused by the carbon-based microstructures) can form one or more signalsignatures indicative of the material, or condition of the material,into which the sensor is incorporated.

Time variance or deviation (TDEV) (referring to the time stability ofphase x versus observation interval r of the measured clock source; thetime deviation thus forms a standard deviation type of measurement toindicate the time instability of the signal source) of frequency shiftsin the returned RF signals 112 (such as that shown in a signalsignature) can correspond to time variant changes in the environment ofthe sensor and/or time variant changes in the sensor itself.Accordingly, signal processing systems (such as any one or more of thevehicle central processing unit 116, the vehicle sensor data receivingunit 118, and/or the vehicle actuators control unit 120, etc.) can beconfigured to analyze signals (such as the emitted RF signals 110 andreturned RF signals 112) associated with the sensors according to TDEVprinciples. Results of such analysis (such as a signature analysis) canbe delivered to the vehicle central processing unit 116, which (in turn)can communicate commands to the vehicle actuators control unit 120 forappropriate responsive action. In some configurations such responsiveaction by the actuators 122 can involve at least some human driverinput, while in other configurations the vehicle condition detectionsystem 100 can function entirely in a self-contained manner allowing fora so-equipped vehicle to address component performance issues as theyarise in an entirely driverless setting. In addition, the vehiclecentral processing unit 116 may electronically communicate with one ormore upstream components 113 (e.g., computational equipment associatedwith racing applications housed in stationary areas) and/or a racingmission control unit 119 responsible for intake and/or processing of alldata associated with the tuned RF resonance components 108.

FIG. 2 depicts a signal processing system 200 that analyzes emittedand/or returned RF signals that are frequency-shifted and/or attenuatedby sensors formed of carbon-containing tuned RF resonance materials, inaccordance with one embodiment. As an option, the signal processingsystem 200 may be implemented in the context of any one or more of theembodiments set forth in any previous and/or subsequent figure(s) and/ordescription thereof. Of course, however, the signal processing system200 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, FIG. 2 shows a block diagram of a signal processing system200, which can include surface sensors 260 and embedded sensors 270, anyone or more of which may electronically communicate with the otherconcerning environmental changes 250 for a so-equipped vehicle(referring to a vehicle equipped with the surface sensors 260 and theembedded sensors 270). The signal processing system 200 may also includea transceiver 214, a signature analysis module 254, and a vehiclecentral processing unit 216, any one or more of which may be inelectronic communication with the other.

In some implementations, the embedded sensors 270 (which can be embeddedwithin materials such as tire plies) can employ and/or be powered byself-powered telemetry including tribological energy generators (notshown in FIG. 2 ) also incorporated within the material enclosed therespective sensor. Accordingly, the tribological energy generators cangenerate usable electric current and/or power by harvesting staticcharge buildup between, for example, a rotating tire or wheel and thepavement it contacts, to power a resonant circuit (to be described infurther detail herein), which can then resonate to emit a RF signal at aknown frequency. As a result, an externally-mounted transceiver unit(such as that mounted within each wheel well of a vehicle) can emit RFsignals which are further propagated by the resonant circuits that aretribologically-powered and embedded in the plies of a tire body in thisconfiguration. Frequency shifts and/or attenuation of the magnitude ofthe emitted signals are likewise received and analyzed, for example, bya signature analysis module 254 and/or a vehicle central processing unit216.

Self-powered telemetry (referring to collection of measurements or otherdata at remote or inaccessible points and their automatic transmissionto receiving equipment for monitoring) can be incorporated in vehicletires. Self-powering telemetry, as referred to herein, includesexploiting tribological charge generation inside a tire, storage of thatcharge, and later discharge of the stored charge to or through aresonant circuit, to make use of the “ringing” (referring to oscillationof the resonant circuit responsible for further emission of RF signals)that occurs during discharge of the resonant circuit (referring to anelectric circuit consisting of an inductor, represented by the letter L,and a capacitor, represented by the letter C, connected together, usedto generate RF signals at a particular frequency or frequencies).

Ping stimulus can be provided, generally, in one of two possibleconfigurations of the presently disclosed vehicle component weardetection systems, including reliance on signals or ‘pings’ generated bya stimulus source, such as a conventional transceiver, located outsidethe tire (or other vehicle component intended for monitoring regardingwear from ongoing use) such as being incorporated within each wheel wellof a so-equipped vehicle; or usage of an intra-tire (referring to alsobeing embedded in the tire plies, similar to the sensors havingcarbon-based microstructures) tribological energy generation devicesthat harvest energy resultant from otherwise wasted frictional energybetween the rotating wheel and/or tire and the ground or pavement incontact therewith. Tribology, as commonly understood and as referred toherein, implies the study of the science and engineering of interactingsurfaces in relative motion. Such tribological energy generation devicescan provide electrical power to intra-tire resonance devices which inturn self-emit tire property telemetry.

Either of the above-discussed two ‘ping’ stimulus generators orproviders can have complex resonance frequencies (CRf) componentsranging from approximately 10 to 99 GHz (due, for example, resonancefrequency of small dimensions of structures like graphene platelets) aswell as lower frequency resonance in KHz range due to the relativelymuch larger dimensions of the discussed intra-tire resonance. Generally,CRf can be equated to a function of elastomer component innate resonancefrequency, carbon component innate resonance frequency, ratio/ensembleof the constituent components, and the geometry of the intra-tireresonance device.

The signal processing system 200 functions to analyze a signal signature(defined by digitally observing frequency shifting and/or attenuation ofany one or more of the emitted RF signals 210 and/or returned RF signals212) once sensors formed of carbon-based microstructures have beenstimulated. As a result of stimulation with a chirp signal sensor thatresonate at one of the chirp/ping frequencies “respond” by resonating ator near its corresponding tuned frequency, shifting the emittedfrequency, and/or attenuating the amplitude of the emitted signal. Whenan environmental change (such as that resulting in the wear of a tirebody ply and/or tread layer) occurs while the chirp/ping is emitted,“returned” signals can monitored for variations in modulation—eitherhigher or lower than the tuned frequency. Accordingly, the transceiver214 can be configured to receive returned RF signals 212 that arerepresentative of the surfaces that they are pinged on or against, etc.

Of course, it is to be again appreciated that although the context ofFIGS. 1-18 relate predominately to automobile application of split ringresonators, such teachings may also apply equally to other scenarios andindustries detailed herein (including concrete, materials science,aerospace, drone and aerial vehicles, mining materials, oil industrycomponents, etc.). Thus, the teachings herein with respect toautomobiles (and tires in particular) may be applied in the context ofthese other industries, some of which are described in detailedhereinbelow.

The foregoing chirp/ping signals can be emitted (such as by non-audibleRF signal, pulse, vibration and/or the like transmission) by thetransceiver 214. Also, the “return” signals can be received by thetransceiver 214. As shown, chirp signals can occur in a repeatingsequence of chirps (such as, the emitted RF signals 210). For example, achirp signal sequence might be formed of a pattern comprising a 1 GHzping, followed by a 2 GHz ping, followed by a 3 GHz ping, and so on. Theentire chirp signal sequence can be repeated in its entiretycontinuously. There can be brief periods between each ping such that thereturned signals from the resonant materials (returned RF signals 212)can be received immediately after the end of a ping. Alternatively, orin addition, signals corresponding to ping stimulus and signals of theobserved “response” can occur concurrently and/or along the same generalpathway or route. The signature analysis module can employ digitalsignal processing techniques to distinguish signals of the observed“response” from the ping signals. In situations where the returnedresponse comprises energy across many different frequencies (such as,overtones, sidelobes, etc.), a notch filter can be used to filter thestimulus. Returned signals that are received by the transceiver can besent to the signature analysis module 254, which in turn can sendprocessed signals to vehicle central processing unit 216. The foregoingdiscussion of FIG. 2 includes discussion of sensors formed ofcarbon-containing tuned resonance materials and can also refer tosensing laminates as well.

Disclosed sensors may be incorporated into tire layers, e.g., includinglayers of resin can be layered interstitially between additional layersof carbon fiber within tire plies. Each layer of carbon-containing resincan be formulated differently to resonate at a different expected ordesired tuned frequency. The physical phenomenon of material resonationcan be described with respect to a corresponding molecular composition.For example, a layer having a first defined structure, such as a firstmolecular structure will resonate at a first frequency, whereas a layerhaving a second, different molecular structure can resonate at a second,different frequency.

Material having a particular molecular structure and contained in alayer will resonate at a first tuned frequency when that layer is in alow energy state and will resonate at a second different frequency whenthe material in the layer is in an induced higher-energy state. Forexample, material in a layer that exhibits a particular molecularstructure can be tuned to resonate at a 3 GHz when the layer is in anatural, undeformed, low energy state. In contrast, that same layer canresonate at 2.95 GHz when the layer is at least partially deformed fromits natural, undeformed, low energy state. As a result, this phenomenoncan be adjusted to accommodate the needs for detecting, with a highdegree of fidelity and accuracy, even the most minute aberration to, forexample, a tire surface contacting against a road surface such aspavement and experiencing enhanced wear at a certain localized region ofcontact. Race cars racing on demanding race circuits (referring tohighly technical, windy tracks featuring tight turns and rapidelevational changes) can benefit from such localized tire wear ordegradation information to make informed tire-replacement decisions,even in time-sensitive race-day conditions.

The frequency-shifting phenomenon referred to above (such astransitioning from resonating at a frequency of 3 GHz to 2.95 GHz) maybe shown and discussed with reference to FIGS. 24B1-24B2, which will bediscussed hereinbelow.

Carbon-containing materials (such as those including carbon-basedmicrostructures) tuned to demonstrate a specific resonance frequencyupon being pinged by a RF signal can be tuned to exhibit a particularresonance profile by tailoring specific compounds that make up thematerials to have particular electrical impedances. Different electricalimpedances in turn correspond to different frequency response profiles.

Impedance describes how difficult it is for an alternating (AC) currentto flow through an element. In the frequency domain, impedance is acomplex number having a real component and an imaginary component due tothe structures behaving as inductors. The imaginary component is aninductive reactance (the opposition of a circuit element to the flow ofcurrent due to that element's inductance or capacitance; largerreactance leads to smaller currents for the same voltage applied)component X_(L), which is based on the frequency f and the inductance Lof a particular structure:

X _(L)=2 πfL  (Eq. 1)

As the received frequency increases, the reactance also increases suchthat at a certain frequency threshold the measured intensity (amplitude)of the emitted signal can attenuate. Inductance L is affected by theelectrical impedance Z of a material, where Z is related to the materialproperties of permeability μ, and permittivity c by the relationship:

$\begin{matrix}{{Z = {\sqrt{\frac{\mu^{\prime} + {j\mu^{''}}}{\varepsilon^{\prime} + {j\varepsilon^{''}}}} = \sqrt{\frac{\mu_{0}}{\varepsilon_{0}}}}},} & \left( {{Eq}.2} \right)\end{matrix}$

Thus, tuning of material properties changes the electrical impedance Z,which affects the inductance L and consequently affects the reactanceX_(L).

Carbon-containing structures such as those disclosed by Anzelmo, et al.,in U.S. Pat. No. 10,428,197 entitled “Carbon and Elastomer Integration”issued on Oct. 1, 2019, incorporated herein by reference in its entiretywith different inductances can demonstrate different frequency responses(when used to create sensors for the aforementioned systems). That is, acarbon-containing structure with a high inductance L (being based onelectrical impedance Z) will reach a certain reactance at a lowerfrequency than another carbon-containing structure with a lowerinductance.

The material properties of permeability, permittivity and conductivitycan also be considered when formulating a compound to be tuned to aparticular electrical impedance. Still further, it is observed that afirst carbon-containing structure will resonate at a first frequency,whereas second carbon-containing structure will resonate at a secondfrequency when that structure is under tension-inducing conditions, suchas when the structure is slightly deformed (such as, thereby slightlychanging the physical characteristics of the structure).

Example carbon-containing structures (e.g., as shown in FIGS. 18A-18Y)that may resonate at a first frequency, which can be correlated to anequivalent electrical circuit comprising a capacitor C₁ and an inductorL₁. The frequency f₁ is given by the equation:

$\begin{matrix}{f_{1} = \frac{1}{2\pi\sqrt{L_{1}C_{1}}}} & \left( {{Eq}.3} \right)\end{matrix}$

Deformation of the carbon-containing structure may, in turn, change theinductance and/or capacitance of the structure. The changes can becorrelated to an equivalent electrical circuit comprising a capacitor C₂and an inductor L₂. The frequency f₂ is given by the equation:

$\begin{matrix}{f_{2} = \frac{1}{2\pi\sqrt{L_{2}C_{2}}}} & \left( {{Eq}.4} \right)\end{matrix}$

FIG. 3 illustrates a signature classification system 300, in accordancewith one embodiment. As an option, the signature classification system300 may be implemented in the context of any one or more of theembodiments set forth in any previous and/or subsequent figure(s) and/ordescription thereof. Of course, however, the signature classificationsystem 300 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

The signature classification system 300 processes signals received fromsensors formed of carbon-containing tuned resonance materials. Thesignature classification system 300 can be implemented in any physicalenvironment or weather condition. FIG. 3 relates to incorporating tunedresonance sensing materials into automotive components for classifyingsignals (such as, signatures) detected by, classified and/or receivedfrom sensors installed in vehicles. A ping signal of a selected pingfrequency is transmitted at operation 302. The ping signal generationmechanism and the ping transmission mechanism can be performed by anyknown techniques. For example, a transmitter module can generate aselected frequency of 3 GHz, and radiate that signal using an antenna ormultiple antennae. The design and location of the tuned antenna (such asmounted on and/or within any one or more of the wheel wells or avehicle) can correspond to any tuned antenna geometry, material and/orlocation such that the strength of the ping is sufficient to induce (RF)resonance in proximate sensors. Several tuned antennae are disposed uponor within structural members that are in proximity to correspondingsensors. As such, when a proximal surface sensor is stimulated by aping, it may resonate back with a signature. That signature can bereceived (at operation 304) and stored in a dataset comprising receivedsignatures 310. A sequence of transmission of a ping, followed byreception of a signature, can be repeated in a loop.

The ping frequency can be changed (operation 308) in iterative passesthrough the loop. Accordingly, as operation 304 is performed in theloop, operation 304 can store signatures 312, including a firstsignature 312 ₁, a second signature 312 ₂, up to an N^(th) signature 312_(N). The number of iterations can be controlled by decision 306. Whenthe “No” branch of decision 306 is taken (such as, when there are nofurther additional pings to transmit), then the received signatures canbe provided (at operation 314) to a digital signal processing module(such as, an instance of signature analysis module 254 shown in FIG. 2). The digital signal processing module classifies the signatures(operation 316) against a set of calibration points 318. Thecalibrations points can be configured to correspond to particular pingfrequencies. For example, calibration points 318 can include a firstcalibration point 3201 that can correspond to a first ping and firstreturned signature near 3 GHz, a second calibration point 3202 that cancorrespond to a second ping and second returned signature near 2 GHz,and so on for any integer value “N” calibration points (up to a N^(th)calibration point 320 _(N)).

At operation 320, classified signals are sent to a vehicle centralprocessing unit (such as, the vehicle central processing unit 116 ofFIG. 1 ). The classified signals can be relayed by the vehicle centralprocessing unit 116 to an upstream repository that hosts a computerizeddatabase configured to host and/or run machine learning algorithms.Accordingly, a vast amount of stimulus related to signals, classifiedsignals, and signal responses can be captured for subsequent dataaggregation and processing. The database can be computationallyprepared, referring to as being “trained”, provided a given set ofsensed measurements that can be correlated to conditions or diagnosesrelated to vehicular performance, such as tire degradation due torepeated use. Should, during the operation of the vehicle, the measureddeflection (such as, air pressure) of a particular portion of an airfoilcomponent differ from the measured deflection (such as, air pressure) ofa different portion of the airfoil component, a potential diagnosis maybe that one tire is underinflated and therefore causing vehicle rideheight to be non-uniform, resulting in airflow over, on, and/or aroundthe vehicle to demonstrate proportionate non-uniformities, as detectedby deflection on the airfoil component. Other potential conditions ordiagnoses can be determined by the machine learning system as well. Theconditions and/or diagnoses and/or supporting data can be returned tothe vehicle to complete a feedback loop. Instrumentation in the vehicleprovides visualizations that can be acted upon (such as, by a driver orby an engineer).

FIG. 4 depicts a series of tire condition parameters that are sensedfrom changes in RF resonance of various layers of carbon-containingtuned RF resonance materials, in accordance with one embodiment.

FIG. 4 depicts a series of tire condition parameters 400 that are sensedfrom changes in RF resonance of various layers of carbon-containingtuned RF resonance materials, in accordance with one embodiment. As anoption, the tire condition parameters 400 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the tire condition parameters 400 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, FIG. 4 illustrates various physical characteristics or aspects(tire condition parameters 400) pertaining to incorporating tunedresonance sensing materials into automotive components (such as tires).Here, the figure is presented with respect to addressing deployment ofsurvivable sensors in tires, including non-pneumatic tires as well aspneumatic tires. The construction of the tires may correspond to radialtires, bias ply tires, tubeless tires, solid tires, run-flat tires, etc.Tires may be used in any sorts of vehicles and/or equipment and/oraccessories pertaining to vehicles. Such vehicles may include aircraft,all-terrain vehicles, automobiles, construction equipment, dump trucks,earthmovers, farm equipment, forklifts, golf carts, harvesters, lifttrucks, mopeds, motorcycles, off-road vehicles, racing vehicles, ridinglawn mowers, tractors, trailers, trucks, wheelchairs, etc. The tiresmay, in addition or alternative to that presented, be used innon-motorized vehicles, equipment and accessories such as bicycles,tricycles, unicycles, lawnmowers, wheelchairs, carts, etc.

The parameters shown in FIG. 4 are as an example, and other variants mayexist or otherwise be prepared to target specific desirable performancecharacteristics of many conceivable end-use scenarios, including trucktires designed to offer increased longevity (at the potential expense ofroad adhesion), or soft racing tires designed to provide maximum roadadhesion (at the potential expense of lifespan).

Various carbon structures may be used in different formulations withother non-carbon materials integrated into tires, which then undergomechanical analysis to determine their respective characteristics of thetires. Some of these characteristics can be determined empirically bydirect testing, while other characteristics are determined based onmeasurements and data extrapolation. For example, rolling uniformity canbe determined by sensing changes in force when the tire is subjected torolling over a uniform surface such as a roller, whereas tread life isbased on an abrasion test over a short period, the results of whichshort term test are extrapolated to yield a predicted tread life value.

More tire characteristics can be measured, but some of these measurementtechniques can be physically destructive to the tire, and thus measuredat a desired point in the life of the tire. In contrast, usingsurvivable sensors embedded in tires allows for such otherwisedestructive measurements to be made throughout the entire lifetime ofthe tire. For example, detection of response signals based on RF signalspinged against sensors embedded in tires can be used for such sensing.Moreover, each body ply and/or tread layer of a tire can, as discussedherein, include durable (also referred to as “survivable”) sensors thatare tuned to resonate at a particular frequency.

Ply used in a tire can be formulated to combine carbon-containingstructures with other materials to achieve a particular materialcomposition that exhibits desired performance (such as handling andlongevity) characteristics. The natural resonance frequency (orfrequencies) of the particular material composition can be subjected tospectral analysis to develop a spectral profile for the particularmaterial composition. This spectral profile can be used as a calibrationbaseline for that material. When the body ply and/or tread layer of thetire undergoes deformation, the spectral profile changes, which spectralprofile changes can be used as additional calibration points (such asthe calibration points 318). Many such calibration points can begenerated by testing, and such calibration points can in turn be used togauge deformation.

Analysis of the spectral response results in quantitative measurementsof many tire parameters. The tire parameters that can be determined fromsignature analysis, for example, can include tread life 422, handling ata first temperature 428, handling at a second temperature 426, rollingeconomy at a first temperature 430, rolling economy at a secondtemperature 432, rolling uniformity 436, and braking uniformity 438.

Responses, such as those spectrally represented based on return pingsignals received from sensors embedded in materials in tire ply, can berepresentative of the deformation observed. That is, a certain type oftire deformation will correspond with a certain type of specificresponse, such that a mapping between responses or response types can bedone to degradation types. Moreover, time-variant changes in thespectral response of a tire as it undergoes in-situ deformation can beused to determine many ambient conditions. In tires that are constructedusing multiple ply, each body ply and/or tread layer can be formulatedto exhibit a particular tuned frequency or range of frequencies. Forexample, FIG. 5 (shown hereinbelow) shows a schematic diagram forconstructing a tire from multiple ply, each of which has as different aparticular tuned frequency or range of frequencies.

FIG. 5 depicts a schematic diagram 500 of an apparatus used for tuningmultiple plies of a tire by selecting carbon-containing tuned RFresonance materials from separate and independent reactors forincorporation into the body of a single tire assembly, in accordancewith one embodiment. As an option, the schematic diagram 500 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the schematic diagram 500 may beimplemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

The schematic diagram 500 may be used for fine-adjustment, or tuning, ofmultiple body plies and/or tread layers of a tire by selectingcarbon-containing tuned resonance materials for incorporation into atire assembly or structure, which can be implemented in any environment.FIG. 5 illustrates how to mix different carbons into tire compositeformulations that are in turn assembled into a multi-ply tire. Theresulting multi-ply tire exhibits the various resonance-sensitive andfrequency-shifting characteristics.

Multiple reactors (such as, reactor 5521, reactor 5522, reactor 5523,and reactor 5524) each produce (or otherwise transport or provide) aparticular carbon additive/filler to the network that is tuned to yielda particular defined spectral profile. The carbon additives (such as,first tuned carbons 554, second tuned carbons 556, third tuned carbons558, and fourth tuned carbons 560) can mixed with other (carbon-based ornon-carbon based) compositions 550. Any known techniques can be used tomix, heat, pre-process, post-process or otherwise combine the particularcarbon additives with the other compositions. Mixers (such as, mixer5621, mixer 5622, mixer 5623, and mixer 5624) are presented to show howdifferent tuned carbons can be introduced into various components of atire. Other techniques for tire assembly may involve other constructiontechniques and/or other components that comprise the tire. Any knowntechniques for multi-ply tires can be used. Moreover, the spectralprofile of a particular body ply and/or tread layer (such as a group ofbody plies and/or tread layers 568, including a body ply and/or treadlayer 5681, a body ply and/or tread layer 5682, a body ply and/or treadlayer 5683, and a body ply and/or tread layer 5684) can be determinedbased on the characterization of a particular body ply and/or treadlayer formulation. For example, based on a stimulus and responsecharacterization, a first body ply and/or tread layer formulation (suchas, body ply and/or tread layer formulation 5641) might exhibit a firstspectral profile, whereas a second body ply and/or tread layerformulation (such as, body ply and/or tread layer formulation 5642)might exhibit a second spectral profile.

The resulting different formulations (such as, body ply and/or treadlayer formulation 5641, body ply and/or tread layer formulation 5642,body ply and/or tread layer formulation 5643, and body ply and/or treadlayer formulation 5644), each of which body ply and/or tread layerexhibits a corresponding spectra profile, are used in the different bodyply and/or tread layer that are formed into a tire assembly 566.

FIG. 6 depicts sets of example condition signatures 600 that may beemitted from new tires formed of layers of carbon-containing tuned RFresonance materials, in accordance with one embodiment. As an option,the example condition signatures 600 may be implemented in the contextof any one or more of the embodiments set forth in any previous and/orsubsequent figure(s) and/or description thereof. Of course, however, theexample condition signatures 600 may be implemented in the context ofany desired environment. Further, the aforementioned definitions mayequally apply to the description below.

FIG. 6 shows a second set of example condition signatures 600 that areemitted from tires formed of layers of carbon-containing tuned resonancematerials. The example condition signatures 600 or any aspect thereofmay be emitted in any environment. FIG. 6 illustrates multiple body plyand/or tread layer (such as, body ply and/or tread layer #1, body plyand/or tread layer #2, and body ply and/or tread layer #3) of a newtire. The term “ply”, as used in this example and elsewhere withreference to any one or more of the presented implementations, can referto a ply or layer within a body of the tire, or—alternatively—a layer ofthe tire tread protruding radially outward away from the body of thetire intended for contact with hard pavement, or the earth for off-roadtires). In one embodiment, the first body ply and/or tread layer may beformulated (referring to being created with a specific formula) withtuned carbons such that the first body ply and/or tread layer resonatesat 1.0 GHz when stimulated with a 1.0 GHz ping stimulus (such as, thefirst ping 602). Similarly, the second body ply and/or tread layer isformulated with tuned carbons such that the second body ply and/or treadlayer resonates at 2.0 GHz when stimulated with a 2.0 GHz ping stimulus(such as, the second ping 604). Further, the third body ply and/or treadlayer is formulated with tuned carbons such that the third body plyand/or tread layer resonates at 3.0 GHz when stimulated with a 3.0 GHzping stimulus (such as, the third ping 606). As shown by first response608, second response 610, and third response 614, all three-body plyand/or tread layer are responsive at their respective tuned frequencies.

A transceiver antenna can be positioned in and/or on the wheel well ofthe corresponding tire (and/or in any location near the split ringresonator). Systems handling any such generated response signals can beconfigured to distinguish from other potential responses arising fromthe other surfaces, such as the remaining non-target tires of thevehicle, for example. For example, even though the right front tiremounted on the right front wheel of the vehicle might respond to a pingthat is emitted from a transceiver antenna located in the left frontwheel well of the vehicle, the response signal from the right front tirewill be significantly attenuated (and recognized as such) as compared tothe response signals from the left front tire of the vehicle. In variousembodiments, the positioning of the transceiver antenna could be withininches of the split ring resonator, or could be 5-10 meters (or evenfarther) as needed. Such positioning may be a function of the power ofthe emitter receiver.

When the transceiver antenna is located in the wheel well of acorresponding tire, the response from the corresponding tire will beattenuated with respect to the ping stimulus. For example, the responsefrom the corresponding tire can be attenuated with respect to the pingstimulus by 9 decibels (−9 dB) or more or can be attenuated with respectto the ping stimulus by 18 decibels (−18 dB) or more or can beattenuated with respect to the ping stimulus by 36 decibels (−36 dB) ormore or can be attenuated with respect to the ping stimulus by 72decibels (−72 dB) or more. In some cases, a ping signal generator isdesigned to be combined with a transceiver antenna located in the wheelwell so as to cause the ping response of a corresponding tire to beattenuated by not more than 75 dB (−75 dB).

FIG. 7 depicts sets of example condition signatures 700 that may beemitted from new tires formed of layers of carbon-containing tuned RFresonance materials, in accordance with one embodiment. As an option,the example condition signatures 700 may be implemented in the contextof any one or more of the embodiments set forth in any previous and/orsubsequent figure(s) and/or description thereof. Of course, however, theexample condition signatures 700 may be implemented in the context ofany desired environment. Further, the aforementioned definitions mayequally apply to the description below.

As shown, the third set of example condition signatures 700 are emittedfrom tires after wear-down of some of the carbon-containing tunedresonance materials. As an option, one or more variations of examplecondition signatures 700 or any aspect thereof may be implemented in thecontext of the architecture and functionality of the implementationsdescribed herein. The example condition signatures 700 or any aspectthereof may be emitted in any environment.

In this example, the tire has undergone wear. More specifically, theoutermost body ply and/or tread layer has been worn away completely. Assuch, a ping stimulus at 1.0 GHz would not result in a response from theoutermost ply. This is shown in the chart as a first responseattenuation 702. As the tire continues to undergo tread wear, pingresponses from the next body ply and/or tread layer and ping responsesfrom the next successive body ply and/or tread layer and so on will beattenuated, which attenuation can be used to measure total tread wear ofthe tire. As an alternative, the same tuned carbons can be used in allplies. The tread wear of the tire as well as other indications can bedetermined based on the returned signal signatures from the tire.

FIG. 8 depicts a top-down schematic view 800 of an example split-ringresonator (split ring resonator) configuration including two concentricsplit ring resonators, in accordance with one embodiment. As an option,the top-down schematic view 800 may be implemented in the context of anyone or more of the embodiments set forth in any previous and/orsubsequent figure(s) and/or description thereof. Of course, however, thetop-down schematic view 800 may be implemented in the context of anydesired environment. Further, the aforementioned definitions may equallyapply to the description below.

As shown, FIG. 8 is a top view of two layers, where each layer hosts asplit ring resonator (split ring resonator), e.g., forming an examplesplit-ring resonator (split ring resonator) configuration including twoconcentric split ring resonators. As used herein, split ring resonators(split ring resonators) consist of a pair of concentric rings, disposedon a dielectric substrate, where each ring has slits (e.g., due to aprinted pattern). When an array of split ring resonators is excited bymeans of a time varying magnetic field, the structure behaves as aneffective medium with negative effective permeability in a narrow bandaround the split ring resonator resonance point. Many geometries arepossible, e.g., such that dimensions and/or spacings between each splitring resonator including dimensions “a,” “r”, and/or “c” are selected toachieve particular corresponding spectral response. For example, “a” maybe approximately 1 mm, “r” may be 2 mm, and “c” may be approximately 0.6mm. These dimensions may correspond to producing a desired and/orexpected spectral response, e.g., resulting in a relatively wider and/orbroader signal response rather than a narrow and/or notched response,facilitating improved spectral analysis leading to improvedcost-efficiency in using spectral analysis tools (such as a spectrumanalyzer). In addition, or the alternative, any of the dimensions may befurther adjusted to achieve particular desired end-result objectives,e.g., applications in racing circuits compared to off-road applications,etc. In one embodiment, a particular geometry may involve gaps betweenconcentric rings. Such gaps may produce a capacitance which incombination with the inductance inherent in the pair of concentric ringsintroduces a change in the resonance of the ensemble.

A printable, sheet-oriented, cylinder-type, split ring resonator designcan be built out of any electrically-conducting materials, includingmetals, electrically-conducting non-metals, dielectric materials,semiconducting materials, etc. In addition to tuning based on theselection and/or treatment of electrically-conducting materials, splitring resonators can be tuned by varying the geometry such that theeffective permittivity accordingly tuned. Effective permittivity as afunction of the geometry of a split ring resonator is given in Eq. 5.

$\begin{matrix}{\mu_{eff} = {1 - \frac{\frac{\pi r^{2}}{a^{2}}}{1 + \frac{2l\sigma_{1}i}{\omega r\mu_{0}} - \frac{3{lc}_{0}^{2}}{{\pi\omega}^{2}r^{3}{\ln\left( \frac{2c}{d} \right)}}}}} & \left( {{Eq}.5} \right)\end{matrix}$

where a is the spacing of the cylinders, ω is the angular frequency, μ0is the permeability of free space, r is the radius, d is the spacing ofthe concentric conducting sheets, l is a stacking length, c is thethickness of a ring, and a is the resistance of unit length of thesheets measured around the circumference.

In some situations, the value of a (e.g., the spacing of the cylindersof a cylindrical split ring resonator) can be made relatively small suchthat the concentric rings absorb EM radiation within a relatively narrowfrequency range. In other situations, the value of a can be maderelatively large such that the concentric rings each absorb EM radiationat frequencies that are separated by a wide range. In some situations,differently-sized split ring resonators can be disposed on differentsurfaces of the tire. In some situations, the differently-sized splitring resonators that are disposed on different surfaces of the tire canbe used to take measurements of tire conditions (e.g., temperature,aging, wear, etc.).

In some embodiments, the materials that form the split ring resonatorare composite materials. Each split ring resonator can be configured toany particular desired tuned response to EM stimulation. At leastinasmuch as split ring resonators are designed to mimic the resonanceresponse of atoms (though on a much larger scale, and at lowerfrequencies), the larger scale of split ring resonators as compared withatoms allows for more control over the resonance response. Moreover,split ring resonators are much more responsive than ferromagneticmaterials found in nature. The pronounced magnetic response of splitring resonators carries with it a significant advantage over heavier,naturally occurring materials.

FIG. 9 depicts a schematic diagram 900 showing a complete tirediagnostics system and apparatus for tire wear sensing throughimpedance-based spectroscopy, in accordance with one embodiment. As anoption, the schematic diagram 900 may be implemented in the context ofany one or more of the embodiments set forth in any previous and/orsubsequent figure(s) and/or description thereof. Of course, however, theschematic diagram 900 may be implemented in the context of any desiredenvironment. Further, the aforementioned definitions may equally applyto the description below.

As shown, the schematic diagram 900 of a tire, such as a pneumaticrubber tire filled with air or nitrogen gas (N₂), can includetraditional tire components including a body 920, an inner liner 912, abead filler region 922, a bead 916, one or more belt plies 904, 906,908, and 910, tread 902, and impedance-based spectroscopy wear sensingprinted electronics 918 (alternatively sensors including carbon-basedmicrostructures for signal frequency shift and attenuation monitoring bya resonator embedded within any one or more of the belt plies 904-910).

As shown here, a wireless strain sensor can be placed on surfaces or onthe sides of the inner liner (or be embedded within) to monitor the tirecondition for automobile safety, (such as to detect damaged tires). Tiredeformation or strain monitoring can (indirectly) provide informationrepresentative of a degree of friction between the tires and contactingroad surfaces, which can then be used for the optimization of automobiletire control systems. The tire information can be wirelessly transmittedto a receiver positioned in the wheel well (and/or any location near thesplit ring resonator) based on a resonant sensor platform. It is to beappreciated that the receiver could be potentially located anywhere thatis not opaque to radio frequency (wireless) signaling.

FIG. 10 depicts a schematic diagram 1000 relating to tire informationtransferred via telemetry into a navigation system, as well as equipmentfor manufacturing printed carbon-based materials, in accordance with oneembodiment. As an option, the schematic diagram 1000 may be implementedin the context of any one or more of the embodiments set forth in anyprevious and/or subsequent figure(s) and/or description thereof. Ofcourse, however, the schematic diagram 1000 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the schematic diagram 1000 show a system for providing tirewear-related information transferred via telemetry into a navigationsystem and equipment for manufacturing printed carbon-based materials.The schematic diagram 1000 can function with any one or more of thepresently disclosed systems, methods, and materials, such as the sensorsincluding carbon-based microstructures such that a redundant descriptionof the same is omitted. Impedance spectroscopy, also referred to asElectrochemical Impedance Spectroscopy (EIS), refers to a method ofimpedimetric transduction involving the application of a sinusoidalelectrochemical perturbation (potential or current) over a wide range offrequencies when measuring a sample, such as a sensor includingcarbon-based microstructures incorporated within one or more tire beltplies of a tire 1002. Printed carbon-based resonators 1004 can beincorporated within one or more tire components such as the tire beltplies, with each of the printed carbon-based resonators 1004 having thegeneral oval configuration shown, or some other shape or configurationtailored to achieve specific desirable resonance properties suitable forefficient and accurate vehicle component wear detection throughmonitoring of frequency shift and/or attenuation (such as a firstresponse attenuation indicative of the wear of a tire body ply and/ortread layer having a natural resonance frequency of approximately 1.0GHz).

An assembly of rollers 1010 capable of forming the printed carbon-basedresonators 1004 includes a repository 1012 (such as a vat) ofcarbon-based microstructures and/or microstructural material (such asgraphene), an anilox roller 1014 (referring to a hard cylinder, usuallyconstructed of a steel or aluminum core which is coated by an industrialceramic whose surface contains millions of very fine dimples, known ascells), a plate cylinder 1016, and an impression cylinder 1018. Inoperation, graphene extracted from the repository 1012 can be rolled,pressed, stretched, or otherwise fabricated by the rollers of theassembly of rollers 1010 into the printed carbon-based resonators 1004.No registration (referring to alignment) of the printed carbon-basedresonators 1004 may be needed for functioning of the schematic diagram1000.

As such, any combination of the aforementioned features can be used tomanufacture a tire that has a resonator (referring to actual or“equivalent” tank), LC and/or resonant circuit, where carbon-containingmicrostructures themselves can resonate in response to emitted RFsignals from a transceiver, and/or from energy supplied by an advancedenergy source, such that other sensors, disposed into or onto any one ormore components such as the tread, a ply or plies, an inner liner, etc.of the tire can demonstrate frequency-shifting or signal attenuationproperties or behavior. The described resonator is not necessarilyrequired to be embodied as an actual electrical and/or integratedcircuit (IC). The described resonator can be realized simply as tunedcarbon-containing microstructures, to thus avoid common deteriorationconcerns that may arise when implementing traditional discrete circuitryin decomposable materials, such as tire tread layers. Such resonatorscan resonate in response to an externally-supplied ‘ping’ (such as thatsupplied by a transceiver located in the wheel well of vehicle), or theresonator can respond to being charged by a co-located (referring towithin the same tire tread layer, but possibly at a different locationwithin that tire tread layer), self-powered, self-pinging capabilityfacilitated by any variations or any number of power or chargegenerators (such as thermoelectric generators, piezoelectric energygenerators, triboelectric energy generators, etc.).

At any time when the tire is rolling or otherwise undergoingdeformation, any of the described resonators (and other resonatorsand/or resonant circuits) can be configured to emit and/or further emitoscillating RF signals (or other forms of electromagnetic radiation,depending on the overall configuration). As a vehicle tire experienceswear resultant from usage (such as on or off-road driving), tire treadlayers in contact with pavement or ground (earth) may experiencedeformation, either instantaneously or over time (such as that observedfrom being “squished”, referring to at least partial flattening ofsections of the exposed vehicle tire tread layers during rotation orrolling, and/or from lateral motion as experienced during turning,etc.), therefore resultant signal frequency-shift and/or attenuationbehavior may change pursuant to such “squishing” as associated signalscan oscillate over one or more known amplitude ranges. In addition, orin the alternative, as the tire undergoes deformation, observed signalscan oscillate within a known frequency range corresponding to aparticular resonator, allowing for precise and accurate identificationof the type of deterioration occurring while it is occurring, ratherthan requiring the driver, passengers, and/or other vehicle occupants toexit the vehicle, while it is stationary, to observe tire treadconditions. Such a frequency-shifting oscillation may be observable as afrequency shift back and forth between two or more frequencies withinthe known frequency range.

A wireless-capable strain sensor (such as a geometric measure ofdeformation representing the relative displacement between particles ina material body that may be caused by external constraints or loads)positioned on sides of the inner liner can monitor tire condition forautomobile safety (such by detecting damaged tires). Additionally, tiredeformation or strain monitoring can indirectly provide informationrelated to the degree of friction between tires and road surface, whichcan then be used for the optimization of automobile tire controlsystems. Such tire information can be wirelessly transmitted to areceiver (and/or transceiver) positioned in the wheel hub based on aresonant sensor (such as an impedance spectroscopy, IS, sensor)platform.

FIG. 11 depicts a schematic diagram 1100 relating to tire informationtransferred via telemetry into a navigation system, as well as equipmentfor manufacturing printed carbon-based materials, in accordance with oneembodiment. As an option, the schematic diagram 1100 may be implementedin the context of any one or more of the embodiments set forth in anyprevious and/or subsequent figure(s) and/or description thereof. Ofcourse, however, the schematic diagram 1100 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

In one embodiment, the schematic diagram 1100 may relate to a resonantserial number-based digital encoding system for determining wear ofvehicle tires through ply-print encoding. The resonant serialnumber-based digital encoding system may be incorporated and/or functionwith any of the presently disclosed systems, methods, and sensors. Theresonant serial number-based digital encoding system offers digitalencoding of tires through ply-print encoding and thus offerscradle-to-the-grave (referring to a full lifespan) of tracking of tires(and related performance metrics) and a usage profile without requiringtraditional electronic devices susceptible to routine wear-and-tear inthe tires.

Resonant serial number digital encoding of tire through tire tread layerprinting may facilitate, in some implementations, cradle-to-grave tiretracking of tires and usage without necessarily requiring the presenceof electronics within the tires. For example, along with tire wearsensing accomplished through impedance spectroscopy, additionalresonators may be digitally encoded onto, for example, one or moreprinted patterns for serial numbers used for telemetry tracking. As aresult, so-equipped vehicles can track tread wear, miles driven (e.g.,in total), and tire age without requiring radio-frequency identification(RFID) technology.

Along with tire wear sensing thru Impedance Spectroscopy (IS) and/orElectrochemical Impedance Spectroscopy (EIS), additional resonators canbe digitally encoded onto a printed pattern to provide a recognizableserial number for telemetry-based tire performance tracking. By beingprinted onto the body ply and/or tread layer incrementally, tiresincorporating the discussed printed carbon-based resonators can beinnately serialized.

FIG. 12 depicts a schematic diagram 1200 for resonant serialnumber-based digital encoding of vehicle tires through tire tread layerand/or tire body ply-print encoding, in accordance with one embodiment.As an option, the schematic diagram 1200 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the schematic diagram 1200 may be implemented in the context ofany desired environment. Further, the aforementioned definitions mayequally apply to the description below.

As shown, the serial number “6E” is shown encoded in aspecially-prepared array of printed carbon resonators configured toresonate according to the ‘ping’ stimulus-response diagram 1212 allowingfor convenient and reliable identification of that particular body plyand/or tread layer of the so-equipped vehicle tire.

FIG. 13 illustrates resonance mechanisms 1300 that contribute to theensemble phenomenon arising from different proximally-present resonatortypes, in accordance with one embodiment. As an option, the resonancemechanisms 1300 may be implemented in the context of any one or more ofthe embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the resonance mechanisms1300 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

In one embodiment, the resonance mechanisms 1300 may be used toillustrate use of split ring resonators (split ring resonators) asresonance devices that contribute to the ensemble phenomenon arisingfrom different proximally-present resonator types. The figure shows theinner surface 1301 of a tire, where the inner surface has two split ringresonators (e.g., split ring resonator 1303A and split ring resonator1303B), each of which split ring resonator forms a circuit configuration1305 that can be tuned to attenuate a signal at a particular frequencyand/or to attenuate within a particular range of frequencies. In thisembodiment, circuit configuration 1305 is shown as a geometric patternthat corresponds to a substantially-circular split ring resonator;however, alternative circuit configurations can have different geometricpatterns (e.g., cylinders, ellipses, rectangles, ovals, squares, etc.),and as such, any conceivable geometric configuration is possible.Variations of the geometric configurations can be selected based on theimpact on resonation capabilities of the geometric pattern. Inparticular, and as shown, the geometric pattern can compriseself-assembled carbon-based particles having various agglomerationpatterns (e.g., agglomeration pattern 1306, agglomeration pattern 1308,and agglomeration pattern 1310), any one or more of which can constitutea concentrated region 1304 that can impact the resonation performance ofmaterials within which carbon-based microstructures are incorporated. Anagglomeration pattern and/or a series of agglomeration patterns may alsoimpact the resonation performance of materials within which carbon-basedmicrostructures are incorporated.

In various configurations, the carbon-based microstructures may beformed, at least in part, by graphene. In this context, graphene mayrefer to an allotrope of carbon in the form of a single layer of atomsin a two-dimensional hexagonal lattice in which one atom forms eachvertex. Co-location and/or juxtaposition of multiple of such hexagonallattices into more complex structures introduces further resonanceeffects. For example, juxtaposition 1302 of two sheets or platelets ofgraphene may resonate between themselves at a frequency that isdependent on the length, width, spacing, thickness, shape of thespacing, and/or other physical characteristics of the sheets orplatelets and/or their relative juxtaposition to each other.

Table 1 depicts one possible chord of attenuations arising from theensemble effect. As shown in the table, each of the structures has adifferent resonant frequency domain that corresponds to its scaledesignation.

TABLE 1 Ensemble effect examples Structure Scale Designation ResonantFrequency Domain Printed Pattern Macro-scale Lower GHz (e.g., split ringresonator geometry) Agglomeration pattern Meso-scale Higher GHzJuxtaposition of graphene Micro-scale Very high GHz sheets or plateletsMolecule Nano-scale THz

Any number of different split ring resonators can be printed onto asurface of a tire. Moreover, any number of different sizes of split ringresonators can be printed onto any of the surfaces of a tire. The choiceof materials and/or the size and/or other structural or dimensionalcharacteristics of a particular split ring resonator can be used tocontrol the resonation frequency of that particular resonator splitring. A series of differently-sized split ring resonators can be printedsuch that the pattern corresponds to a digitally encoded value.Stimulating the series of differently-sized split ring resonators withvia electromagnetic signal communication, for example, sweeping througha range from 8 GHz to 9 GHz or similar, and measuring the attenuationresponse through a range of the return may lead to a recognizableencoded serial number. Many different encoding schemes are possible, andas such, the non-limiting example of Table 2 is merely for illustration.

TABLE 2 Example encoding scheme Size (outer diameter) 1 mm 2 mm 2.5 mm 3mm 4 mm 5 mm 6 mm 7 mm Bit Assignment 8 7 6 5 4 3 2 1 CalibratedAttenuation Point (GHz) 8.890 8.690 8.655 8.570 8.470 8.380 8.350 8.275Encoded 6E split ring resonator pattern Present Present Present PresentPresent Encoded 6E bit pattern 0 1 1 0 1 1 1 0 Encoded 4E split ringresonator pattern Present Present Present Present Encoded 4E bit pattern0 1 0 0 1 1 1 0 Encoded E1 split ring Present Present Present Presentresonator pattern Encoded El bit pattern 1 1 1 0 0 0 0 1

FIG. 14 is an example temperature sensor 1400 including one or more ofthe presently disclosed split ring resonators, in accordance with oneembodiment. As an option, the example temperature sensor 1400 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the example temperature sensor 1400 may beimplemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

In one implementation, the example temperature sensor 1400 may include asection 1402 of a tire body (e.g., as shown in FIG. 9 ) with multipletire plies. The example temperature sensor 1400 may detect a temperature1408 of a tire ply, e.g., in which the example temperature sensor 1400is incorporated. In one implementation, the tire sensor may include aceramic material 1404 (e.g., organized as a matrix), and one or moresplit ring resonators 1406, such as shown in FIG. 8 and elsewhere in thepresent disclosure). Each of the one or more split ring resonators 1406may have a natural resonance frequency (e.g., as shown in FIG. 16 ) thatmay shift in response to one or more of a change in an elastomericproperty or a change in the temperature of the respective tire. Anelectrically-conductive layer 1410 may be dielectrically separated froma respective split ring resonator of the one or more split ringresonators 1406. In some implementations, the example temperature sensor1400 may be produced and shipped without being incorporated in a tire,such that later incorporation within a tire and/or tire ply is possible.

In addition, or in an alternative embodiment, the example temperaturesensor 1400 may be incorporated into a system (not shown in FIG. 14 )configured to detect tire strain (e.g., as shown in FIG. 16 ) in avehicle. The system may include an antennae (e.g., as discussed in thepresent disclosure relating to emission and/or propagation ofelectromagnetic signals) disposed on one or more of the vehicle or avehicle component. The antennae may be configured to output anelectromagnetic ping. The system may also include a tire having a body(e.g., as shown in FIG. 9 ) formed of one or more tire plies. Any one ormore of the tire plies may include split-ring resonators (split ringresonators), e.g., as discussed in the present disclosure. In oneimplementation, each split ring resonator may have a natural resonancefrequency configured to proportionately shift (e.g., as shown in FIG. 16) in response to a change in an elastomeric property of a respective oneor more tire plies, e.g., reversible deformation, stress, and/or strain.

In some implementations, the described system may function to detectchanges in physical properties of materials outside of configurationsrelating to tires and/or vehicles, e.g., automobiles and trucks. Forexample, the system may detect changes in surface temperature of anairplane wing and/or other type of airfoil, e.g., associated withspacecraft and/or the like. Also, the system may permit for instanceswhere the one or more split ring resonators 1406 may be removablyadhered onto patients in a hospital setting, such that body temperaturereadings of the respective patient may be obtained without the usage ofconventional thermal sensors (e.g., relying on radiative heat transfertechnology, etc.). In any of these examples, as well as others, such asystem may detect a physical property associated with a surface.

In one implementation, the system may include a single antennaeconfigured to output an electromagnetic ping and one or more flexiblesubstrates. Each of the flexible substrates may include a first sideincluding a plurality of split-ring resonators (split ring resonators)(e.g., such as the one or more split ring resonators 1406) disposed onthe flexible substrate. Each split ring resonator may have a naturalresonance frequency that may proportionately shift (e.g., as shown inFIG. 16 ) in response to a change in an elastomeric property of arespective one or more tire plies. The elastomeric property may includeone or more of a reversible deformation, stress, strain, or temperature.In this way, the system may generate an absorption profile (e.g.,referring to unique changes in absorption phenomena of theelectromagnetic ping output by the antennae). The system may include asecond side positioned opposite to the first side. The second side mayattach to the surface. The single antenna may analyze data associatedwith the absorption profile and output a topography of the physicalproperty.

FIG. 15 is a graph 1500 of measured resonant signature signal intensity(in decibels, dB) relative to height (in millimeters, mm) of tire treadlayer loss, in accordance with one embodiment. As an option, the graph1500 may be implemented in the context of any one or more of theembodiments set forth in any previous and/or subsequent figure(s) and/ordescription thereof. Of course, however, the graph 1500 may beimplemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

As shown here, carbon-containing microstructures and/or microstructuralmaterials can be incorporated into sensors or, in some configurations,entire layers of one or more tire treads at a given concentration level,or multiple dissimilar concentration levels (in each of the one or moretire tread layers) to achieve the unique deterioration profile shown.That is, the measure resonance signature (referring to the identifying“signature” of a particular tire tread layer in question) can be‘pinged’, as so described herein, by one or more RF signals todemonstrate the attenuation of that emitted signal as shown.

A new tire tread layer can be configured to indicate a signal intensity(measured in decibels, dB) of approximately 0. That intensity can changeproportionate to the extent of deterioration of that tire tread layer.For instance, a 2 mm height loss of a tire tread layer, presumedly thetire tread layer in contact with pavement, can correspond with themeasure resonant signature signal intensity profile shown. A ‘ping’signal at 6.7 GHz can be measured at an intensity level of about 9 dB,etc., and so on and so forth.

Accordingly, unique concentration levels, chemistries, dispersions,distributions and/or the like of the carbon-containing microstructurescan be embedded (or, in some cases, placed on one or more surfaces of)tire tread layers to achieve a unique and readily identifiable measuredresonant signature signal intensity as shown. A user of such a systemcan therefore immediately be notified to the exact extent and locationof tire tread wear as it occurs during driving, rather than beingrestricted to observe the tires while the vehicle is in a stationarycondition, a process that can be both time-consuming and cumbersome.

FIG. 16 is a graph 1600 of measured resonant signature signal intensity(in decibels, dB) relative to the natural resonance frequency of splitring resonators showing resonance response shift proportionate to tireply deformation, in accordance with one embodiment. As an option, thegraph 1600 may be implemented in the context of any one or more of theembodiments set forth in any previous and/or subsequent figure(s) and/ordescription thereof. Of course, however, the graph 1600 may beimplemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

In one embodiment, the graph 1600 shows measured resonant signaturesignal intensity (in decibels, dB) against the natural resonancefrequency of split-ring resonator(s) (split ring resonators)incorporated into tire treads and/or tire plies (e.g., as discussed inthe present disclosure), in accordance with one embodiment. As shownhere, carbon-containing and/or carbonaceous microstructures and/ormicrostructural materials can be incorporated into sensors or, in someconfigurations, entire layers of one or more tire treads at a givenconcentration level, or multiple dissimilar concentration levels (ineach of the one or more tire tread layers) to achieve the uniquedeterioration profile shown. That is, the measure resonance signature(referring to the identifying “signature” of a particular tire treadlayer in question) can be ‘pinged’, as so described herein, by one ormore RF signals to demonstrate the shift of that emitted signal asshown, e.g., representative and/or proportionate to an extent ofreversible tire deformation, e.g., stress and/or strain (as may beencountered in drifting scenarios). In this way, split ring resonator“response” signal behavior can be modeled as a function of tiredeformation, e.g., strain (associated with drifting), allowing for acomplete picture of tire condition and performance. Real-world scenariosresulting in lateral tire stiction loss may include drifting and/orhydroplaning, e.g., implying phenomena that occurs when a layer of waterbuilds between the wheels of the vehicle and the road surface, leadingto a loss of traction that prevents the vehicle from responding tocontrol inputs. If hydroplaning occurs to all contact wheelssimultaneously, the vehicle becomes, in effect, an uncontrolled sled.Usage of the presently disclosed split ring resonators and/or resonatorsin combination with antennae and/or signal processing equipment mayeffectively eliminate the need to rely on conventional hydroplaningdetection techniques, e.g., through usage of a vibration detection unitcoupled with surfaces of a tire which may deteriorate and becomecompromised through extended usage. In addition, FIG. 16 shows spectralresponse (in signal decibels) associated with lateral tire movementencountered during striction loss while drifting. In real-worldscenarios, such as temporary stiction loss may be audibly heard througha high-pitched “screech,” as opposed to other sounds heard during rapidforward rotation only. This type of periodic stiction loss (prior to thedrifting vehicle regaining stiction and/or traction) may be exhibited(not shown in FIG. 16 ) as a periodic and/or cyclical shift in thenatural resonance frequency of corresponding split ring resonators.Further yet, with respect to FIG. 16 , “screech” type circumstances maybe visually depicted by minor periodic and/or cyclical shifts infrequency of the various troughs and/or peaks of the curves.

As can be seen, the real-time multi-modality resonator supports methodsfor measuring stiction using resonant materials-containing sensors forelastomer property change detection. In one setting, one or moreresonant materials-containing sensors for elastomer property changedetection are disposed in a location proximal to a transducer. Astimulation signal may be emitted so as to excite the one or moreresonant materials-containing sensors for elastomer property changedetection. The emissions comprise electromagnetic energy that spans aknown frequency range. A calibration signal is captured under a knownstiction condition. After receiving return signals that comprise, atleast in part, frequencies that are responsive to the stimulationsignal, various signal processing techniques are applied to the returnsignal. For example, various signal processing techniques are applied tothe return signal to compare with respect to the stimulation signal.Wherever frequencies and/or amplitude of the return signal differs fromthe calibration signal, a corresponding interfacial indirectpermittivity (e.g., at the interface between a tire and the drivingsurface) is calculated. Absolute and/or relative values of theinterfacial indirect permittivity are correlated to a stictional value(e.g., using a calibration table). Changes in the stictional value overtime are in turn correlated to road and/or tire conditions.

The static and/or dynamic values that make up the aforementionedcalibration signal and/or calibration table can be based at least inpart on analysis of the stimulation signal, and/or analysis of anenvironment proximal to the transducer. Moreover, the aforementionedcalibration signal and/or calibration table can encompass permittivitycalibration signals, permeability calibration signals, temperaturecalibration signals, vibration calibration signals, doping calibrationsignals, etc. In one implementation, calibration procedures may beperformed under known and/or controlled environmental conditions, e.g.,dry pavement and in clear weather, to generate baseline data at variousforward-facing angular velocities (such that the test vehicle is onlymoving directly forward with no lateral skidding and/or slidingmovement). This baseline data then serves as one or more calibrationcurves from which deformation values may be subsequently compared and/orcalculated. In this way, clear performance changes may be observedrelative to the initial unstretched (baseline) calibration curve, e.g.,as shown in FIG. 16 .

Whenever and wherever the return signal differs from the calibrationsignal further analysis of the return signal with respect to thestimulation signal can serve to identify which of the frequencies of thereturn signal are different than the calibration signal. The differencescan be observed/measured as an attenuation of a frequency or frequencieswith respect to the calibration signal. Additionally, or alternatively,the differences can be observed/measured as a frequency shift (as shownin FIG. 16 relative to data corresponding stretched at 0.5%, etc.) ofpeaks with respect to peaks of the calibration signal.

FIG. 17 is a graph 1700 of signal intensity relative to chirp signalfrequency for split ring resonators that may resonate corresponding toan encoded serial number, in accordance with one embodiment. As anoption, the graph 1700 may be implemented in the context of any one ormore of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the graph 1700may be implemented in the context of any desired environment. Further,the aforementioned definitions may equally apply to the descriptionbelow.

In one embodiment, the graph 1700 shows use of split ring resonantstructures that are configured to resonate in a manner that correspondsto an encoded serial number. Such a pattern of split ring resonantstructures can be printed on tires or other elastomers. As shown, theencoded serial number “E1” is shown by the presence of split ringresonators of four different sizes. The graph 1700 shows EM stimulus ina range of about 8 GHz to about 9 GHz, whereas the response is shown asattenuation in a range from about −8 dB to about −18 dB. Stimulating theseries of different sized split ring resonators with via electromagneticsignal communication across the range and measuring the S-parameters ofthe return across the range, leads to convenient and reliableidentification of that particular printed pattern. It follows then that,if a unique pattern is printed onto each one of a run of tires, and ifthe pattern is associated with an encoded serial number, then adetermination of the specific tire can be made based on the pattern'sresponse to the EM interrogation.

More specifically, if a unique pattern is printed onto each one of a runof tires, and if the pattern is associated with an encoded serialnumber, then a determination of the specific tire can be made based onmeasured S-parameters (e.g., S-parameter ratios that correspond toattenuation) in response to EM interrogation over an EM stimulus in arange corresponding to the encoding scheme. In the example of FIG. 17 ,the attenuations fall in a range from about −8 dB to about −18 dBhowever, in other measurements the attenuations fall in a range of about−1 dB to about −9 dB. In other measurements the attenuations fall in arange of about −10 dB to about −19 dB. In other measurements theattenuations fall in a range of about −20 dB to about −35 dB. Inempirical experimentation, the attenuations are substantiallyindependent of the number of differently-configured resonators that areproximally collocated on a tire surface. More particularly, in someexperimentation, the attenuations may be particularly pronounced whenthe resonators are proximally collocated on a tire surface that may beon the tread-side of a steel belt (e.g., in a steel belted radial tire).

The foregoing encoding and printing techniques can be used in tires andother elastomer-containing components. In some cases, printing theresonators is carried out at relatively high temperatures and/or withchemical agents (e.g., catalysts) such that chemical bonds are formedbetween the carbon atoms of the resonators and the elastomers. Thechemical bonds that are formed between the carbon atoms of theresonators and the elastomers contribute to ensemble effect, and assuch, calibration curves may be taken to account for the type and extentof the aforementioned chemical bonds.

The elastomer may contain any one or more types of rubber. Isoprene, forexample, is a common rubber formulation. Isoprene has its own single C—Cbonds and double bonds between the other molecular elements in theligands. Additional double carbon bonds formed by the high-temperatureprinting of the split ring resonators has the effect of increasedconductivity, which effect can be exploited to form larger, lowerfrequency resonators. Additionally, or alternatively, agglomerations canbe tuned into specific sizes, which would give rise to overtones thatcontribute to the ensemble effect, which in turn results in very highsensitivity given EM interrogation in a tuned range. In some cases, theresponse of the materials to EM interrogation is sufficientlydiscernable such that the age or other aspect of the elastomer's healthcan be determined (e.g., by comparison to one or more calibrationcurves).

More specifically, as elastomers age, the molecular spacing changes andcoupling and/or percolation of energy decreases correspondingly, thusshifting the response frequencies as the conductive localities becomemore and more isolated with respect to adjacent localities. In somecases, attenuation and/or return signal strength will change at specificfrequencies. Such changes can be determined over time, and the changescan be used to construct calibration curves.

The design of tires supports many possible locations for printing of thesplit ring resonators. As examples, split ring resonators can be locatedon any inner surface of a tire, including but not limited to the capply, and/or on or near the steel belts (e.g., on the tread side of asteel belt), and/or on or near a radial ply, and/or on the sidewall,and/or on the bead chafers, and/or on the beads, etc.

Use of the split ring resonator techniques are not limited to onlytires. The techniques can be applied to any elastomer-containingcomponents such belts and hoses. Moreover, the use of the split ringresonator techniques is not limited to only vehicles. That is, sinceconsumables exist in organic powertrain and/or drive train components ina wide range of motive devices (e.g., in industrial mechanical systems),the split ring resonator techniques can be applied to such consumablesas well. Some aspects of wear phenomena are a consequence of friction,heat, heat cycling and corrosion, any of which can result in and/oraccelerate changes in the molecular structure of the materials. Changesin the molecular structure of the materials is detectable under EMinterrogation. More specifically, by calculating a frequency shift, aparticular sample's response (e.g., an aged sample's response) under aparticular EM interrogation regime with respect to a calibration curve,the age or health of the material can be assessed based on the magnitudeof the frequency shift.

FIGS. 18A through 18Y depict carbonaceous materials used as a formativematerial to produce any of the presently disclosed resonators (e.g.,split ring resonators), in accordance with one embodiment. As an option,FIGS. 18A through 18Y may be implemented in the context of any one ormore of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, FIGS. 18Athrough 18Y may be implemented in the context of any desiredenvironment. Further, the aforementioned definitions may equally applyto the description below.

As shown, FIG. 18A through FIG. 18Y depict carbon-based materials,growths, agglomerates, aggregates, sheets, particles and/or the like,such as those self-nucleated in-flight in a reaction chamber or reactorfrom a carbon-containing gaseous species such as methane (CH₄), asdisclosed by Stowell, et al., in U.S. patent application Ser. No.16/785,020 entitled “3D Self-Assembled Multi-Modal Carbon-BasedParticle” filed on Feb. 7, 2020, the contents of which are herebyincorporated by reference for all purposes.

The shown carbon-based nanoparticles and aggregates can be characterizedby a high degree of “uniformity” (such as a high mass fraction ofdesired carbon allotropes), a high degree of “order” (such as a lowconcentration of defects), and/or a high degree of “purity” (such as alow concentration of elemental impurities), in contrast to the loweruniformity, less ordered, and lower purity particles achievable withconventional systems and methods.

The nanoparticles produced using the methods described herein cancontain multi-walled spherical fullerenes (MWSFs) or connected MWSFs andhave a high uniformity (such as, a ratio of graphene to MWSF from 20% to80%), a high degree of order (such as, a Raman signature with anI_(D)/I_(G) ratio from 0.95 to 1.05), and a high degree of purity (suchas, the ratio of carbon to other elements (other than hydrogen) isgreater than 99.9%). The nanoparticles produced using the methodsdescribed herein contain MWSFs or connected MWSFs, and the MWSFs do notcontain a core composed of impurity elements other than carbon. Theparticles produced using the methods described herein can be aggregatescontaining the nanoparticles described above with large diameters (suchas greater than 10 μm).

Conventional methods have been used to produce particles containingmulti-walled spherical fullerenes with a high degree of order but canlead to end products with a variety of shortcomings. For example, hightemperature synthesis techniques lead to particles with a mixture ofmany carbon allotropes and therefore low uniformity (such as less than20% fullerenes relative to other carbon allotropes) and/or smallparticle sizes (such as less than 1 μm, or less than 100 nm in somecases). Methods using catalysts can lead to products that include thecatalyst elements and therefore have relatively lower purity (referringto less than 95% carbon to other elements) as well. These undesirableproperties also often lead to undesirable electrical properties of theresulting carbon particles (such as, electrical conductivity of lessthan 1,000 S/m).

The carbon nanoparticles and aggregates described herein can becharacterized by Raman spectroscopy that is indicative of the highdegree of order and uniformity of structure. The uniform ordered and/orpure carbon nanoparticles and aggregates described herein can beproduced using relatively high speed, low cost improved thermal reactorsand methods, as described below.

The term “graphene”, as both commonly understood and as referred toherein, implies an allotrope of carbon in the form of a two-dimensional,atomic-scale, hexagonal lattice in which one atom forms each vertex. Thecarbon atoms in graphene are sp²-bonded. Additionally, graphene has aRaman spectrum with two main peaks: a G-mode at approximately 1580 cm⁻¹and a D-mode at approximately 1350 cm⁻¹ (when using a 532 nm excitationlaser).

The term “fullerene”, as both commonly understood and as referred toherein, implies a molecule of carbon in the form of a hollow sphere,ellipsoid, tube, or other shapes. Spherical fullerenes can also bereferred to as Buckminsterfullerenes, or buckyballs. Cylindricalfullerenes can also be referred to as carbon nanotubes. Fullerenes aresimilar in structure to graphite, which is composed of stacked graphenesheets of linked hexagonal rings. Fullerenes may also contain pentagonal(or sometimes heptagonal) rings.

The term “multi-walled fullerene”, as both commonly understood and asreferred to herein, implies fullerenes with multiple concentric layers.For example, multi-walled nanotubes (MWNTs) contain multiple rolledlayers (concentric tubes) of graphene. Multi-walled spherical fullerenes(MWSFs) contain multiple concentric spheres of fullerenes.

The term “nanoparticle”, as both commonly understood and as referred toherein, implies a particle that measures from 1 nm to 989 nm. Thenanoparticle can include one or more structural characteristics (suchas, crystal structure, defect concentration, etc.), and one or moretypes of atoms. The nanoparticle can be any shape, including but notlimited to spherical shapes, spheroidal shapes, dumbbell shapes,cylindrical shapes, elongated cylindrical type shapes, rectangularand/or prism shapes, disk shapes, wire shapes, irregular shapes, denseshapes (such as, with few voids), porous shapes (such as, with manyvoids), etc.

The term “aggregate”, as both commonly understood and as referred toherein, implies a plurality of nanoparticles that are connected togetherby Van der Waals forces, by covalent bonds, by ionic bonds, by metallicbonds, or by other physical or chemical interactions. Aggregates canvary in size considerably, but in general are larger than about 500 nm.

A carbon nanoparticle can include two (2) or more connected multi-walledspherical fullerenes (MWSFs) and layers of graphene coating theconnected MWSFs and can be formed to be independent of a core composedof impurity elements other than carbon. A carbon nanoparticle, asdescribed herein, can include two (2) or more connected multi-walledspherical fullerenes (MWSFs) and layers of graphene coating theconnected MWSFs. In such a configuration, where the MWSFs do not containa void (referring to a space with no carbon atoms greater thanapproximately 0.5 nm or greater than approximately 1 nm) at the center.The connected MWSFs can be formed of concentric, well-ordered spheres ofsp²-hybridized carbon atoms (which is in favorable contrast toconventional spheres of haphazardly-ordered, non-uniform, amorphouscarbon particles, which can otherwise fail to achieve any one or more ofthe unexpected and favorable properties disclosed herein).

The nanoparticles containing the connected MWSFs have an averagediameter in a range from 5 to 500 nm, or from 5 to 250 nm, or from 5 to100 nm, or from 5 to 50 nm, or from to 500 nm, or from 10 to 250 nm, orfrom 10 to 100 nm, or from 10 to 50 nm, or from 40 to 500 nm, or from 40to 250 nm, or from 40 to 100 nm, or from 50 to 500 nm, or from 50 to 250nm, or from 50 to 100 nm.

The carbon nanoparticles described herein form aggregates, wherein manynanoparticles aggregate together to form a larger unit. A carbonaggregate can a plurality of carbon nanoparticles. A diameter across thecarbon aggregate can be a range from 10 to 500 μm, or from to 500 μm, orfrom 100 to 500 μm, or from 250 to 500 μm, or from 10 to 250 μm, or from10 to 100 μm, or from 10 to 50 μm. The aggregate can be formed from aplurality of carbon nanoparticles, as defined above. Aggregates cancontain connected MWSFs, such as those with a high uniformity metric(such as a ratio of graphene to MWSF from 20% to 80%), a high degree oforder (such as a Raman signature with an I_(D)/I_(G) ratio from 0.95 to1.05), and a high degree of purity (such as greater than 99.9% carbon).

Aggregates of carbon nanoparticles, referring primarily to those withdiameters in the ranges described above, especially particles greaterthan 10 μm, are generally easier to collect than particles or aggregatesof particles that are smaller than 500 nm. The ease of collectionreduces the cost of manufacturing equipment used in the production ofthe carbon nanoparticles and increases the yield of the carbonnanoparticles. Particles greater than 10 μm in size also pose fewersafety concerns compared to the risks of handling smaller nanoparticles,such as, potential health and safety risks due to inhalation of thesmaller nanoparticles. The lower health and safety risks, thus, furtherreduce the manufacturing cost.

A carbon nanoparticle, in reference to that disclosed herein, can have aratio of graphene to MWSFs from 10% to 90%, or from 10% to 80%, or from10% to 60%, or from 10% to 40%, or from 10% to 20%, or from 20% to 40%,or from 20% to 90%, or from 40% to 90%, or from 60% to 90%, or from 80%to 90%. A carbon aggregate has a ratio of graphene to MWSFs is from 10%to 90%, or from 10% to 80%, or from 10% to 60%, or from 10% to 40%, orfrom 10% to 20%, or from 20% to 40%, or from 20% to 90%, or from 40% to90%, or from 60% to 90%, or from 80% to 90%. A carbon nanoparticle has aratio of graphene to connected MWSFs from 10% to 90%, or from 10% to80%, or from 10% to 60%, or from 10% to 40%, or from 10% to 20%, or from20% to 40%, or from 20% to 90%, or from 40% to 90%, or from 60% to 90%,or from 80% to 90%. A carbon aggregate has a ratio of graphene toconnected MWSFs is from 10% to 90%, or from 10% to 80%, or from 10% to60%, or from 10% to 40%, or from 10% to 20%, or from 20% to 40%, or from20% to 90%, or from 40% to 90%, or from 60% to 90%, or from 80% to 90%.

Raman spectroscopy can be used to characterize carbon allotropes todistinguish their molecular structures. For example, graphene can becharacterized using Raman spectroscopy to determine information such asorder/disorder, edge and grain boundaries, thickness, number of layers,doping, strain, and thermal conductivity. MWSFs have also beencharacterized using Raman spectroscopy to determine the degree of orderof the MWSFs.

Raman spectroscopy is used to characterize the structure of MWSFs orconnected MWSFs used in reference to that incorporated within thevarious tire-related plies of tires as discussed herein. The main peaksin the Raman spectra are the G-mode and the D-mode. The G-mode isattributed to the vibration of carbon atoms in sp²-hybridized carbonnetworks, and the D-mode is related to the breathing of hexagonal carbonrings with defects. In some circumstances, defects may be present, yetmay not be detectable in the Raman spectra. For example, if thepresented crystalline structure is orthogonal with respect to the basalplane, the D-peak will show an increase. Alternatively, if presentedwith a perfectly planar surface that is parallel with respect to thebasal plane, the D-peak will be zero.

When using 532 nm incident light, the Raman G-mode is typically at 1582cm⁻¹ for planar graphite, however, can be downshifted for MWSFs orconnected MWSFs (such as, down to 1565 cm 1 or down to 1580 cm⁻¹). TheD-mode is observed at approximately 1350 cm⁻¹ in the Raman spectra ofMWSFs or connected MWSFs. The ratio of the intensities of the D-modepeak to G-mode peak (such as, the I_(D)/I_(G)) is related to the degreeof order of the MWSFs, where a lower I_(D)/I_(G) indicates a higherdegree of order. An I_(D)/I_(G) near or below 1 indicates a relativelyhigh degree of order, and an I_(D)/I_(G) greater than 1.1 indicates alower degree of order.

A carbon nanoparticle or a carbon aggregate containing MWSFs orconnected MWSFs, as described herein, can have and/or demonstrate aRaman spectrum with a first Raman peak at about 1350 cm⁻¹ and a secondRaman peak at about 1580 cm⁻¹ when using 532 nm incident light. Theratio of an intensity of the first Raman peak to an intensity of thesecond Raman peak (such as, the I_(D)/I_(G)) for the nanoparticles orthe aggregates described herein can be in a range from to 1.05, or from0.9 to 1.1, or from 0.8 to 1.2, or from 0.9 to 1.2, or from 0.8 to 1.1,or from to 1.5, or less than 1.5, or less than 1.2, or less than 1.1, orless than 1, or less than 0.95, or less than 0.9, or less than 0.8.

A carbon aggregate containing MWSFs or connected MWSFs, as definedabove, has a high purity. The carbon aggregate containing MWSFs orconnected MWSFs has a ratio of carbon to metals of greater than 99.99%,or greater than 99.95%, or greater than 99.9%, or greater than 99.8%, orgreater than 99.5%, or greater than 99%. The carbon aggregate has aratio of carbon to other elements of greater than 99.99%, or greaterthan 99.95%, or greater than 99.9%, or greater than 99.5%, or greaterthan 99%, or greater than 90%, or greater than 80%, or greater than 70%,or greater than 60%. The carbon aggregate has a ratio of carbon to otherelements (except for hydrogen) of greater than 99.99%, or greater than99.95%, or greater than 99.9%, or greater than 99.8%, or greater than99.5%, or greater than 99%, or greater than 90%, or greater than 80%, orgreater than 70%, or greater than 60%.

A carbon aggregate containing MWSFs or connected MWSFs, as definedabove, has a high specific surface area. The carbon aggregate has aBrunauer, Emmett and Teller (BET) specific surface area from 10 to 200m²/g, or from 10 to 100 m²/g, or from 10 to 50 m²/g, or from 50 to 200m²/g, or from 50 to 100 m²/g, or from 10 to 1000 m²/g.

A carbon aggregate containing MWSFs or connected MWSFs, as definedabove, has a high electrical conductivity. A carbon aggregate containingMWSFs or connected MWSFs, as defined above, is compressed into a pelletand the pellet has an electrical conductivity greater than 500 S/m, orgreater than 1,000 S/m, or greater than 2,000 S/m, or greater than 3,000S/m, or greater than 4,000 S/m, or greater than 5,000 S/m, or greaterthan 10,000 S/m, or greater than 20,000 S/m, or greater than 30,000 S/m,or greater than 40,000 S/m, or greater than 50,000 S/m, or greater than60,000 S/m, or greater than 70,000 S/m, or from 500 S/m to 100,000 S/m,or from 500 S/m to 1,000 S/m, or from 500 S/m to 10,000 S/m, or from 500S/m to 20,000 S/m, or from 500 S/m to 100,000 S/m, or from 1000 S/m to10,000 S/m, or from 1,000 S/m to 20,000 S/m, or from 10,000 to 100,000S/m, or from 10,000 S/m to 80,000 S/m, or from 500 S/m to 10,000 S/m. Insome cases, the density of the pellet is approximately 1 g/cm 3, orapproximately 1.2 g/cm 3, or approximately 1.5 g/cm 3, or approximately2 g/cm 3, or approximately 2.2 g/cm 3, or approximately 2.5 g/cm 3, orapproximately 3 g/cm 3. Additionally, tests have been performed in whichcompressed pellets of the carbon aggregate materials have been formedwith compressions of 2,000 psi and 12,000 psi and with annealingtemperatures of 800° C. and 1,000° C. The higher compression and/or thehigher annealing temperatures generally result in pellets with a higherdegree of electrical conductivity, including in the range of 12,410.0S/m to 13,173.3 S/m.

The carbon nanoparticles and aggregates described herein can be producedusing thermal reactors and methods. Further details pertaining tothermal reactors and/or methods of use can be found in U.S. Pat. No.9,862,602, issued Jan. 9, 2018, entitled “CRACKING OF A PROCESS GAS”,which is hereby incorporated by reference in its entirety for allpurposes. Additionally, carbon-containing and/or hydrocarbon precursors(referring to at least methane, ethane, propane, butane, and naturalgas) can be used with the thermal reactors to produce the carbonnanoparticles and the carbon aggregates described herein.

The carbon nanoparticles and aggregates described herein are producedusing the thermal reactors with gas flow rates from 1 slm to 10 slm, orfrom 0.1 slm to 20 slm, or from 1 slm to 5 slm, or from 5 slm to 10 slm,or greater than 1 slm, or greater than 5 slm. The carbon nanoparticlesand aggregates described herein are produced using the thermal reactorswith gas resonance times from 0.1 seconds (s) to 30 s, or from 0.1 s to10 s, or from 1 s to 10 s, or from 1 s to 5 s, from 5 s to 10 s, orgreater than 0.1 seconds, or greater than 1 s, or greater than 5 s, orless than 30 s.

The carbon nanoparticles and aggregates described herein can be producedusing the thermal reactors with production rates from 10 g/hr to 200g/hr, or from 30 g/hr to 200 g/hr, or from 30 g/hr to 100 g/hr, or from30 g/hr to 60 g/hr, or from 10 g/hr to 100 g/hr, or greater than 10g/hr, or greater than 30 g/hr, or greater than 100 g/hr.

Thermal reactors (or other cracking apparatuses) and thermal reactormethods (or other cracking methods) can be used for refining,pyrolizing, dissociating or cracking feedstock process gases into itsconstituents to produce the carbon nanoparticles and the carbonaggregates described herein, as well as other solid and/or gaseousproducts (such as, hydrogen gas and/or lower order hydrocarbon gases).The feedstock process gases generally include, for example, hydrogen gas(H²), carbon dioxide (CO²), C¹ to C¹⁰ hydrocarbons, aromatichydrocarbons, and/or other hydrocarbon gases such as natural gas,methane, ethane, propane, butane, isobutane, saturated/unsaturatedhydrocarbon gases, ethene, propene, etc., and mixtures thereof. Thecarbon nanoparticles and the carbon aggregates can include, for example,multi-walled spherical fullerenes (MWSFs), connected MWSFs, carbonnanospheres, graphene, graphite, highly ordered pyrolytic graphite,single-walled nanotubes, multi-walled nanotubes, other solid carbonproducts, and/or the carbon nanoparticles and the carbon aggregatesdescribed herein.

Methods for producing the carbon nanoparticles and the carbon aggregatesdescribed herein can include thermal cracking methods that use, forexample, an elongated longitudinal heating element optionally enclosedwithin an elongated casing, housing, or body of a thermal crackingapparatus. The body can include, for example, one or more tubes or otherappropriate enclosures made of stainless steel, titanium, graphite,quartz, or the like. The body of the thermal cracking apparatus isgenerally cylindrical in shape with a central elongate longitudinal axisarranged vertically and a feedstock process gas inlet at or near a topof the body. The feedstock process gas can flow longitudinally downthrough the body or a portion thereof. In the vertical configuration,both gas flow and gravity assist in the removal of the solid productsfrom the body of the thermal cracking apparatus.

The heating element can include any one or more of a heating lamp, oneor more resistive wires or filaments (or twisted wires), metalfilaments, metallic strips, or rods, and/or other appropriate thermalradical generators or elements that can be heated to a specifictemperature (such a, a molecular cracking temperature) sufficient tothermally crack molecules of the feedstock process gas. The heatingelement can be disposed, located, or arranged to extend centrally withinthe body of the thermal cracking apparatus along the centrallongitudinal axis thereof. In configurations having only one heatingelement can include it placed at or concentric with the centrallongitudinal axis; alternatively, for configurations having multipleheating elements can include them spaced or offset generallysymmetrically or concentrically at locations near and around andparallel to the central longitudinal axis.

Thermal cracking to produce the carbon nanoparticles and aggregatesdescribed herein can be achieved by flowing the feedstock process gasover, or in contact with, or within the vicinity of, the heating elementwithin a longitudinal elongated reaction zone generated by heat from theheating element and defined by and contained inside the body of thethermal cracking apparatus to heat the feedstock process gas to or at aspecific molecular cracking temperature.

The reaction zone can be considered to be the region surrounding theheating element and close enough to the heating element for thefeedstock process gas to receive sufficient heat to thermally crack themolecules thereof. The reaction zone is thus generally axially alignedor concentric with the central longitudinal axis of the body. Thethermal cracking is performed under a specific pressure. The feedstockprocess gas is circulated around or across the outside surface of acontainer of the reaction zone or a heating chamber to cool thecontainer or chamber and preheat the feedstock process gas beforeflowing the feedstock process gas into the reaction zone.

The carbon nanoparticles and aggregates described herein and/or hydrogengas are produced without the use of catalysts. Accordingly, the processcan be entirely catalyst free.

Disclosed methods and systems can advantageously be rapidly scaled up orscaled down for different production levels as may be desired, such asbeing scalable to provide a standalone hydrogen and/or carbonnanoparticle producing station, a hydrocarbon source, or a fuel cellstation, to provide higher capacity systems, such as, for a refineryand/or the like.

A thermal cracking apparatus for cracking a feedstock process gas toproduce the carbon nanoparticles and aggregates described herein includea body, a feedstock process gas inlet, and an elongated heating element.The body has an inner volume with a longitudinal axis. The inner volumehas a reaction zone concentric with the longitudinal axis. A feedstockprocess gas can be flowed into the inner volume through the feedstockprocess gas inlet during thermal cracking operations. The elongatedheating element can be disposed within the inner volume along thelongitudinal axis and is surrounded by the reaction zone. During thethermal cracking operations, the elongated heating element is heated byelectrical power to a molecular cracking temperature to generate thereaction zone, the feedstock process gas is heated by heat from theelongated heating element, and the heat thermally cracks molecules ofthe feedstock process gas that are within the reaction zone intoconstituents of the molecules.

A method for cracking a feedstock process gas to produce the carbonnanoparticles and aggregates described herein can include at least anyone or more of the following: (1) providing a thermal cracking apparatushaving an inner volume that has a longitudinal axis and an elongatedheating element disposed within the inner volume along the longitudinalaxis; (2) heating the elongated heating element by electrical power to amolecular cracking temperature to generate a longitudinal elongatedreaction zone within the inner volume; (3) flowing a feedstock processgas into the inner volume and through the longitudinal elongatedreaction zone (such as, wherein the feedstock process gas is heated byheat from the elongated heating element); and (4) thermally crackingmolecules of the feedstock process gas within the longitudinal elongatedreaction zone into constituents thereof (such as, hydrogen gas and oneor more solid products) as the feedstock process gas flows through thelongitudinal elongated reaction zone.

The feedstock process gas used to produce the carbon nanoparticles andaggregates described herein can include a hydrocarbon gas. The resultsof cracking can, in turn, further include hydrogen in gaseous form (suchas, H 2) and various forms of the carbon nanoparticles and aggregatesdescribed herein. The carbon nanoparticles and aggregates include two ormore MWSFs and layers of graphene coating the MWSFs, and/or connectedMWSFs and layers of graphene coating the connected MWSFs. The feedstockprocess gas is preheated (such as, to 100° C. to 500° C.) by flowing thefeedstock process gas through a gas preheating region between a heatingchamber and a shell of the thermal cracking apparatus before flowing thefeedstock process gas into the inner volume. A gas having nanoparticlestherein is flowed into the inner volume and through the longitudinalelongated reaction zone to mix with the feedstock process gas, to form acoating of a solid product (such as, layers of graphene) around thenanoparticles.

The carbon nanoparticles and aggregates containing multi-walledspherical fullerenes (MWSFs) or connected MWSFs described herein can beproduced and collected without requiring the completion of anypost-processing treatments or operations. Alternatively, somepost-processing can be performed on one or more of the presentlydisclosed MWSFs. Some examples of post-processing involved in making andusing resonant materials include mechanical processing such as ballmilling, grinding, attrition milling, micro fluidizing, and othertechniques to reduce the particle size without damaging the MWSFs. Somefurther examples of post-processing include exfoliation processes(referring to the complete separation of layers of carbon-containingmaterial, such as the creation or extraction of layers of graphene fromgraphite, etc.) including sheer mixing, chemical etching, oxidizing(such as the Hummer method), thermal annealing, doping by addingelements during annealing (such as sulfur and/or nitrogen), steaming,filtering, and lyophilization, among others. Some examples ofpost-processing include sintering processes such as spark plasmasintering (SPS), direct current sintering, microwave sintering, andultraviolet (UV) sintering, which can be conducted at high pressure andtemperature in an inert gas. Multiple post-processing methods can beused together or in a series. The post-processing producesfunctionalized carbon nanoparticles or aggregates containingmulti-walled spherical fullerenes (MWSFs) or connected MWSFs.

Materials can be mixed together in different combinations, quantitiesand/or ratios. Different carbon nanoparticles and aggregates containingMWSFs or connected MWSFs described herein can be mixed together prior toone or more post-processing operations, if any at all. For example,different carbon nanoparticles and aggregates containing MWSFs orconnected MWSFs with different properties (such as, different sizes,different compositions, different purities, from different processingruns, etc.) can be mixed together. The carbon nanoparticles andaggregates containing MWSFs or connected MWSFs described herein can bemixed with graphene to change the ratio of the connected MWSFs tographene in the mixture. Different carbon nanoparticles and aggregatescontaining MWSFs or connected MWSFs described herein can be mixedtogether after post-processing. Different carbon nanoparticles andaggregates containing MWSFs or connected MWSFs with different propertiesand/or different post-processing methods (such as, different sizes,different compositions, different functionality, different surfaceproperties, different surface areas) can be mixed together in anyquantity, ratio and/or combination.

The carbon nanoparticles and aggregates described herein are producedand collected, and subsequently processed by mechanical grinding,milling, and/or exfoliating. The processing (such as, by mechanicalgrinding, milling, exfoliating, etc.) can reduce the average size of theparticles. The processing (such as, by mechanical grinding, milling,exfoliating, etc.) increases the average surface area of the particles.The processing by mechanical grinding, milling and/or exfoliation shearsoff some fraction of the carbon layers, producing sheets of graphitemixed with the carbon nanoparticles.

The mechanical grinding or milling is performed using a ball mill, aplanetary mill, a rod mill, a shear mixer, a high-shear granulator, anautogenous mill, or other types of machining used to break solidmaterials into smaller pieces by grinding, crushing, or cutting. Themechanical grinding, milling and/or exfoliating is performed wet or dry.The mechanical grinding is performed by grinding for some period oftime, then idling for some period of time, and repeating the grindingand idling for a number of cycles. The grinding period is from 1 minute(min) to 20 mins, or from 1 min to 10 mins, or from 3 mins to 8 mins, orapproximately 3 mins, or approximately 8 mins. The idling period is from1 min to 10 mins, or approximately 5 mins, or approximately 6 mins. Thenumber of grinding and idling cycles is from 1 min to 100 mins, or from5 mins to 100 mins, or from 10 mins to 100 mins, or from 5 mins to 10mins, or from 5 mins to 20 mins. The total amount of time of grindingand idling is from 10 mins to 1,200 mins, or from 10 mins to 600 mins,or from 10 mins to 240 mins, or from 10 mins to 120 mins, or from 100mins to 90 mins, or from mins to 60 mins, or approximately 90 mins, orapproximately mins minutes.

The grinding steps in the cycle are performed by rotating a mill in onedirection for a first cycle (such as, clockwise), and then rotating amill in the opposite direction (such as, counterclockwise) for the nextcycle. The mechanical grinding or milling is performed using a ballmill, and the grinding steps are performed using a rotation speed from100 to 1000 rpm, or from 100 to 500 rpm, or approximately 400 rpm. Themechanical grinding or milling is performed using a ball mill that usesa milling media with a diameter from 0.1 mm to 20 mm, or from 0.1 mm tomm, or from 1 mm to 10 mm, or approximately 0.1 mm, or approximately 1mm, or approximately 10 mm. The mechanical grinding or milling isperformed using a ball mill that uses a milling media composed of metalsuch as steel, an oxide such as zirconium oxide (zirconia), yttriastabilized zirconium oxide, silica, alumina, magnesium oxide, or otherhard materials such as silicon carbide or tungsten carbide.

The carbon nanoparticles and aggregates described herein are producedand collected, and subsequently processed using elevated temperaturessuch as thermal annealing or sintering. The processing using elevatedtemperatures is done in an inert environment such as nitrogen or argon.The processing using elevated temperatures is done at atmosphericpressure, or under vacuum, or at low pressure. The processing usingelevated temperatures is done at a temperature from 500° C. to 2,500°C., or from 500° C. to 1,500° C., or from 800° C. to 1,500° C., or from800° C. to 1,200° C., or from 800° C. to 1,000° C., or from 2,000° C. to2,400° C., or approximately 8,00° C., or approximately 1,000° C., orapproximately 1,500° C., or approximately 2,000° C., or approximately2,400° C.

The carbon nanoparticles and aggregates described herein are producedand collected, and subsequently, in post processing operations,additional elements or compounds are added to the carbon nanoparticles,thereby incorporating the unique properties of the carbon nanoparticlesand aggregates into other mixtures of materials.

Either before or after post-processing, the carbon nanoparticles andaggregates described herein are added to solids, liquids or slurries ofother elements or compounds to form additional mixtures of materialsincorporating the unique properties of the carbon nanoparticles andaggregates. The carbon nanoparticles and aggregates described herein aremixed with other solid particles, polymers, or other materials.

Either before or after post-processing, the carbon nanoparticles andaggregates described herein are used in various applications beyondapplications pertaining to making and using resonant materials. Suchapplications including but not limited to transportation applications(such as, automobile and truck tires, couplings, mounts, elastomeric“o”-rings, hoses, sealants, grommets, etc.) and industrial applications(such as, rubber additives, functionalized additives for polymericmaterials, additives for epoxies, etc.).

FIGS. 18A and 18B show transmission electron microscope (TEM) images ofas-synthesized carbon nanoparticles. The carbon nanoparticles of FIG.18A (at a first magnification) and FIG. 18B (at a second magnification)contain connected multi-walled spherical fullerenes (MWSFs) withgraphene layers that coat the connected MWSFs. The ratio of MWSF tographene allotropes in this example is approximately 80% due to therelatively short resonance times. The MWSFs in FIG. 18B areapproximately 5 nm to 10 nm in diameter, and the diameter can be from 5nm to 500 nm using the conditions described above. The average diameteracross the MWSFs is in a range from 5 nm to 500 nm, or from 5 nm to 250nm, or from 5 nm to 100 nm, or from 5 nm to 50 nm, or from 10 nm to 500nm, or from 10 nm to 250 nm, or from 10 nm to 100 nm, or from 10 nm to50 nm, or from 40 nm to 500 nm, or from 40 nm to 250 nm, or from 40 nmto 100 nm, or from 50 nm to 500 nm, or from 50 nm to 250 nm, or from 50nm to 100 nm. No catalyst was used in this process, and therefore, thereis no central seed containing contaminants. The aggregate particlesproduced in this example had a particle size of approximately 10 μm to100 μm, or approximately 10 μm to 500 μm.

FIG. 18C shows the Raman spectrum of the as-synthesized aggregates inthis example taken with 532 nm incident light. The I_(D)/I_(G) for theaggregates produced in this example is from approximately 0.99 to 1.03,indicating that the aggregates were composed of carbon allotropes with ahigh degree of order.

FIG. 18D and FIG. 18E show example TEM images of the carbonnanoparticles after size reduction by grinding in a ball mill. The ballmilling was performed in cycles with a 3-minute (min) counter-clockwisegrinding operation, followed by a 6 min idle operation, followed by a3-min clockwise grinding operation, followed by a 6-min idle operation.The grinding operations were performed using a rotation speed of 400rpm. The milling media was zirconia and ranged in size from 0.1 mm to 10mm. The total size reduction processing time was from 60 mins to 120mins. After size reduction, the aggregate particles produced in thisexample had a particle size of approximately 1 μm to 5 μm. The carbonnanoparticles after size reduction are connected MWSFs with layers ofgraphene coating the connected MWSFs.

FIG. 18F shows a Raman spectrum from these aggregates after sizereduction taken with a 532 nm incident light. The I_(D)/I_(G) for theaggregate particles in this example after size reduction isapproximately 1.04. Additionally, the particles after size reduction hada Brunauer, Emmett and Teller (BET) specific surface area ofapproximately 40 m²/g to 50 m²/g.

The purity of the aggregates produced in this sample were measured usingmass spectrometry and x-ray fluorescence (XRF) spectroscopy. The ratioof carbon to other elements, except for hydrogen, measured in 16different batches was from 99.86% to 99.98%, with an average of 99.94%carbon.

In this example, carbon nanoparticles were generated using a thermalhot-wire processing system. The precursor material was methane, whichwas flowed from 1 slm to 5 slm. With these flow rates and the toolgeometry, the resonance time of the gas in the reaction chamber was fromapproximately 20 second to 30 seconds, and the carbon particleproduction rate was from approximately 20 g/hr.

Further details pertaining to such a processing system can be found inthe previously mentioned U.S. Pat. No. 9,862,602, titled “CRACKING OF APROCESS GAS,” which is hereby incorporated by reference for allpurposes.

Example 1

FIG. 18G, FIG. 18H, and FIG. 18I show TEM images of as-synthesizedcarbon nanoparticles of this example. The carbon nanoparticles containconnected multi-walled spherical fullerenes (MWSFs) with layers ofgraphene coating the connected MWSFs. The ratio of multi-walledfullerenes to graphene allotropes in this example is approximately 30%due to the relatively long resonance times allowing thicker, or more,layers of graphene to coat the MWSFs. No catalyst was used in thisprocess, and therefore, there is no central seed containingcontaminants. The as-synthesized aggregate particles produced in thisexample had particle sizes of approximately 10 μm to 500 μm. FIG. 18Jshows a Raman spectrum from the aggregates of this example. The Ramansignature of the as-synthesized particles in this example is indicativeof the thicker graphene layers which coat the MWSFs in theas-synthesized material. Additionally, the as-synthesized particles hada Brunauer, Emmett and Teller (BET) specific surface area ofapproximately 90 m²/g to 100 m²/g.

Example 2

FIG. 18K and FIG. 18L show TEM images of the carbon nanoparticles ofthis example. Specifically, the images depict the carbon nanoparticlesafter performance of size reduction by grinding in a ball mill. The sizereduction process conditions were the same as those described aspertains to the foregoing FIGS. 18G-18J. After size reduction, theaggregate particles produced in this example had a particle size ofapproximately 1 μm to 5 μm. The TEM images show that the connected MWSFsthat were buried in the graphene coating can be observed after sizereduction. FIG. 18M shows a Raman spectrum from the aggregates of thisexample after size reduction taken with 532 nm incident light. TheI_(D)/I_(G) for the aggregate particles in this example after sizereduction is approximately 1, indicating that the connected MWSFs thatwere buried in the graphene coating as-synthesized had become detectablein Raman after size reduction, and were well ordered. The particlesafter size reduction had a Brunauer, Emmett and Teller (BET) specificsurface area of approximately 90 m²/g to 100 m²/g.

Example 3

FIG. 18N is a scanning electron microscope (SEM) image of carbonaggregates showing the graphite and graphene allotropes at a firstmagnification. FIG. 18O is a SEM image of carbon aggregates showing thegraphite and graphene allotropes at a second magnification. The layeredgraphene is clearly shown within the distortion (wrinkles) of thecarbon. The 3D structure of the carbon allotropes is also visible.

The particle size distribution of the carbon particles of FIG. 18N andFIG. 18O is shown in FIG. 18P. The mass basis cumulative particle sizedistribution 1806 corresponds to the left y-axis in the graph (Q³(x)[%]). The histogram of the mass particle size distribution 1808corresponds to the right axis in the graph (dQ³(x) [%]). The medianparticle size is approximately 33 μm. The 10th percentile particle sizeis approximately 9 μm, and the 90th percentile particle size isapproximately 103 μm. The mass density of the particles is approximately10 g/L.

Example 4

The particle size distribution of the carbon particles captured from amultiple-stage reactor is shown in FIG. 18Q. The mass basis cumulativeparticle size distribution 1814 corresponds to the left y-axis in thegraph (Q³(x) [%]). The histogram of the mass particle size distribution1816 corresponds to the right axis in the graph (dQ³(x) [%]). The medianparticle size captured is approximately 11 μm. The 10th percentileparticle size is approximately 3.5 μm, and the 90th percentile particlesize is approximately 21 μm. The graph in FIG. 18Q also shows the numberbasis cumulative particle size distribution 1818 corresponding to theleft y-axis in the graph (Q⁰(x) [%]). The median particle size by numberbasis is from approximately 0.1 μm to approximately 0.2 μm.

Returning to the discussion of FIG. 18P, the graph also shows a secondset of example results. Specifically, in this example, the particleswere size-reduced by mechanical grinding, and then the size-reducedparticles were processed using a cyclone separator. The mass basiscumulative particle size distribution 1810 of the size-reduced carbonparticles captured in this example corresponds to the left y-axis in thegraph (Q³(x) [%]). The histogram of the mass basis particle sizedistribution 1812 corresponds to the right axis in the graph (dQ³(x)[%]). The median particle size of the size-reduced carbon particlescaptured in this example is approximately 6 μm. The 10th percentileparticle size is from 1 μm to 2 μm, and the 90th percentile particlesize is from 10 μm to 20 μm.

Further details pertaining to making and using cyclone separators can befound in U.S. patent application Ser. No. 15/725,928, filed Oct. 5,2017, titled “MICROWAVE REACTOR SYSTEM WITH GAS-SOLIDS SEPARATION”,which is hereby incorporated by reference in its entirety for allpurposes.

In some cases, carbon particles and aggregates containing graphite,graphene and amorphous carbon can be generated using a microwave plasmareactor system using a precursor material that contains methane, orcontains isopropyl alcohol (IPA), or contains ethanol, or contains acondensed hydrocarbon (such as, hexane). In some other examples, thecarbon-containing precursors are optionally mixed with a supply gas(such as, argon). The particles produced in this example containedgraphite, graphene, amorphous carbon, and no seed particles. Theparticles in this example had a ratio of carbon to other elements (otherthan hydrogen) of approximately 99.5% or greater.

In one particular example, a hydrocarbon was the input material for themicrowave plasma reactor, and the separated outputs of the reactorcomprised hydrogen gas and carbon particles containing graphite,graphene, and amorphous carbon. The carbon particles were separated fromthe hydrogen gas in a multi-stage gas-solid separation system. Thesolids loading of the separated outputs from the reactor was from 0.001g/L to 2.5 g/L.

Example 5

FIG. 18R, FIG. 18S, and FIG. 18T are TEM images of as-synthesized carbonnanoparticles. The images show examples of graphite, graphene, andamorphous carbon allotropes. The layers of graphene and other carbonmaterials can be clearly seen in the images.

The particle size distribution of the carbon particles captured is shownin FIG. 18U. The mass basis cumulative particle size distribution 1820corresponds to the left y-axis in the graph (Q³(x) [%]). The histogramof the mass particle size distribution 1822 corresponds to the rightaxis in the graph (dQ³(x) [%]). The median particle size captured in thecyclone separator in this example was approximately 14 μm. The 10thpercentile particle size was approximately 5 μm, and the 90th percentileparticle size was approximately 28 μm. The graph in FIG. 18U also showsthe number basis cumulative particle size distribution 1824corresponding to the left y-axis in the graph (Q⁰(x) [%]). The medianparticle size by number basis in this example was from approximately 0.1μm to approximately 0.2 μm.

FIG. 18V, FIG. 18W, and FIGS. 18X, and 18Y are images that showthree-dimensional carbon-containing structures that are grown onto otherthree-dimensional structures. FIG. 18V is a 100× magnification ofthree-dimensional carbon structures grown onto carbon fibers, whereasFIG. 18W is a 200× magnification of three-dimensional carbon structuresgrown onto carbon fibers. FIG. 18X is a 1601× magnification ofthree-dimensional carbon structures grown onto carbon fibers. Thethree-dimensional carbon growth over the fiber surface is shown. FIG.18Y is a 10000× magnification of three-dimensional carbon structuresgrown onto carbon fibers. The image depicts growth onto the basal planeas well as onto edge planes.

More specifically, FIGS. 18V—18Y show example SEM images of 3D carbonmaterials grown onto fibers using plasma energy from a microwave plasmareactor as well as thermal energy from a thermal reactor. FIG. 18V showsan SEM image of intersecting fiber 1831 and fiber 1832 with 3D carbonmaterial 1830 grown on the surface of the fibers. FIG. 18W is a highermagnification image (the scale bar is 300 μm compared to 500 μm for FIG.18V) showing the 3D carbon material 1830 on the fiber 1832. FIG. 18X isa further magnified view (scale bar is 40 μm) showing the 3D carbonmaterial 1830 on fiber surface 1835, where the 3D nature of the 3Dcarbon material 1830 can be clearly seen. FIG. 18Y shows a close-up view(scale bar is 500 nm) of the carbon alone, showing interconnectionbetween basal planes of the fiber 1832 and edge planes 1834 of numeroussub-particles of the 3D carbon material grown on the fiber. FIGS.18V-18Y demonstrate the ability to grow 3D carbon on a 3D fiberstructure, such as 3D carbon growth grown on a 3D carbon fiber.

3D carbon growth on fibers can be achieved by introducing a plurality offibers into the microwave plasma reactor and using plasma in themicrowave reactor to etch the fibers. The etching creates nucleationsites such that when carbon particles and sub-particles are created byhydrocarbon disassociation in the reactor, growth of 3D carbonstructures is initiated at these nucleation sites. The direct growth ofthe 3D carbon structures on the fibers, which themselves arethree-dimensional in nature, provides a highly integrated, 3D structurewith pores into which resin can permeate. This 3D reinforcement matrix(including the 3D carbon structures integrated with high aspect ratioreinforcing fibers) for a resin composite results in enhanced materialproperties, such as tensile strength and shear, compared to compositeswith conventional fibers that have smooth surfaces, and which smoothsurfaces typically delaminate from the resin matrix.

Carbon materials, such as any one or more of the 3D carbon materialsdescribed herein, can have one or more exposed surfaces prepared forfunctionalization, such as that to promote adhesion and/or add elementssuch as oxygen, nitrogen, carbon, silicon, or hardening agents.Functionalization refers to the addition of functional groups to acompound by chemical synthesis. In materials science, functionalizationcan be employed to achieve desired surface properties; for instance,functional groups can also be used to covalently link functionalmolecules to the surfaces of chemical devices. The carbon materials canbe functionalized in-situ—that is, on site within the same reactor inwhich the carbon materials are produced. The carbon materials can befunctionalized in post-processing. For example, the surfaces offullerenes or graphene can be functionalized with oxygen- ornitrogen-containing species which form bonds with polymers of the resinmatrix, thus improving adhesion and providing strong binding to enhancethe strength of composites.

Functionalizing surface treatments can be performed on any one or moreof the disclosed carbon-based materials (such as, CNTs, CNO, graphene,3D carbon materials such as 3D graphene) utilizing plasma reactors (suchas, microwave plasma reactors) described herein. Such treatments caninclude in-situ surface treatment during creation of carbon materialsthat can be combined with a binder or polymer in a composite material,or surface treatment after creation of the carbon materials while thecarbon materials are still within the reactor.

Some of the foregoing embodiments include resonators that include aplurality of three-dimensional (3D) aggregates formed ofcarbon-containing material that is embedded within a ply or plies oftire. However, some embodiments include resonators that are printed orotherwise disposed on an inner surface of a tire (e.g., on an innerliner of the tire).

FIG. 19A1 provides a depiction 19A100 of a split ring resonator, orplurality of split ring resonators, being placed in concrete before theconcrete is to be poured into a given structural form, in accordancewith one embodiment. As an option, the depiction 19A100 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the depiction 19A100 may be implemented inthe context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown in FIG. 19A1, split ring resonators can be incorporated intothe concrete pour 1902. A split ring resonator, or a plurality of splitring resonators 1904, can be mixed into the concrete 1906 while in amixing vessel, or a split ring resonator, or a plurality of split ringresonators, can be mixed into the concrete while the concrete ismid-stream during the pouring process.

The split ring resonator, or a plurality of split ring resonators 1904,can be captured within the concrete pour 1902. The split ring resonatorscan be captured within the form in any orientation, but may likelysettle near the bottom of the structural element; for instance, whereany given split ring resonator can be oriented such that the normalvector from the plane of the split ring resonator is substantiallyvertical, or any given split ring resonator can be oriented such thatthe normal vector from the plane of the split ring resonator issubstantially horizontal, or any given split ring resonator can beoriented such that the normal vector from the plane of the split ringresonator is on an angle between vertical and horizontal.

In certain situations, the split ring resonator will be captured withinthe form at a location that is relatively proximal to a form boundary.In other cases, the split ring resonator will end up within the form ata location that is relatively distal to a form boundary. This is becauseof the natural tendencies (e.g., fluid dynamics) of foreign object(e.g., split ring resonators) to locate randomly within a concrete pour1902. Regardless of the location of the split ring resonator in theform, the techniques for pinging a split ring resonator with a signaland for receiving a return signal are operable. More specifically, sincethe signal to noise ratio is so wide (see the 18 dB separation as shownin FIG. 17 ), the return signal from any given split ring resonator atany particular location can be received and processed so as tofacilitate comparison to a calibration signal. This technique can beapplied to various structures, one such example can be seen in FIG. 19A1which illustrates a vertically oriented concrete structural member.

The foregoing example pertains to a vertically-oriented concretestructural member, however the herein-disclosed techniques also applywhen forming a horizontally oriented concrete structural member (or aconcrete structure member at any angle).

FIG. 19A2 provides a depiction 19A200 of a split ring resonator, orplurality of split ring resonators, being placed in concrete before theconcrete is to be poured into a given structural form, in accordancewith one embodiment. As an option, the depiction 19A200 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the depiction 19A200 may be implemented inthe context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

In one embodiment, FIG. 19A2 shows a split ring resonator, or aplurality of split ring resonators 1904 that can be incorporated ontothe concrete pour 1902 when pouring for a slab 1910. A split ringresonator, or a plurality of split ring resonators 1904 can be mixedinto the concrete 1906 while in a mixing vessel, or a split ringresonator, or a plurality of split ring resonators 1904 can be mixedinto the concrete 1906 while the concrete is mid-stream during thepouring process.

The split ring resonator, or a plurality of split ring resonators 1904can be captured within the concrete pour 1902, and within the form atany orientation. For example, any given split ring resonator can beoriented such that the normal vector from the plane of the split ringresonator is substantially vertical, or any given split ring resonatorcan be oriented such that the normal vector from the plane of the splitring resonator is substantially horizontal, or any given split ringresonator can be oriented such that the normal vector from the plane ofthe split ring resonator is on an angle between vertical and horizontal.The split ring resonator, or a plurality of split ring resonators 1904may be, in one embodiment, distributed closer to the walls of thehorizontally-oriented concrete structural member 1914. In certainembodiments, the split ring resonator, or a plurality of split ringresonators 1904 may end up within the form at a location that isrelatively proximal to the top surface of the horizontally-orientedconcrete structural member 1914. In certain other embodiments, the splitring resonator, or a plurality of split ring resonators 1904 mayrelatively be proximal to bottom surface of the horizontally-orientedconcrete structural member 1914. Still yet, the split ring resonator, ora plurality of split ring resonators 1904 may be oriented, integratedinto, and/or affixed to rebar (or other support structure within theconcrete member) such that a location of the split ring resonator, or aplurality of split ring resonators 1904 may be maintained during theconcrete pour 1902 to the concrete member.

In various embodiments, FIGS. 19A1 and 19A2 depict one embodiment of asplit ring resonator, or multiple split ring resonators, being placed inconcrete before the concrete is to be poured into a given structuralform (e.g., vertically-oriented concrete structural member,horizontally-oriented concrete structural member). Further, FIGS. 19A1and 19A2 are presented to illustrate, in one embodiment, how a splitring resonator (e.g., of a ring-type, or of a cylinder-type), or aplurality of split ring resonators 1904 (e.g., of ring-types, or ofcylinder-types, or of combinations thereof) can be incorporated into aconcrete mixture in advance of pouring the concrete into a form. Theform can be of any shape. Strictly as examples, and as shown in FIG.19A1, the form can be configured to receive a pour for avertically-oriented concrete structural member 1912 (e.g., the showncolumn or wall 1908). Additionally, or alternatively, and as shown inFIG. 19A2, the form can be configured to receive a pour for ahorizontally-oriented concrete structural member 1914 (e.g., the shownslab 1910).

Regardless of the location of the split ring resonator in the form(e.g., at the top surface, at the bottom, within the concrete, etc.),the techniques for pinging a split ring resonator with a signal and forreceiving a return signal may be maintained and operable. Morespecifically, since the signal to noise ratio is so wide (see the 18 dBseparation as shown in FIG. 17 ), the return signal from any given splitring resonator at any particular location may be received and processedso as to facilitate comparison to an earlier captured calibrationsignal.

In one embodiment, the aforementioned calibration signal may be capturedonce the pour has cured. Such a calibration signal can be stored in adatabase, and/or any system that holds specified information. At a latertime, the structural member may be interrogated with a ping signal andits then-current return signal can be compared to the correspondingcalibration signal. In one embodiment, a difference between thelater-captured signal and the calibration signal may be indicative of achange in compression between the time that the calibration signal wascaptured and the time that the interrogation is carried out.

A similar approach can be applied in the presence of a plurality ofsplit ring resonators that are dispersed throughout the structuralmember. Specifically, pinging in a region of the structural member wherethere are many split ring resonators in substantially the same locationwould return a calibration signal that can also be stored in a database,or any other system that can store information. Again, at any latertime, the structural member can be interrogated with a ping signal andits then-current return signal can be compared to a correspondingcalibration signal. If a difference is determined between the twosignals, this phenomenon can be indicative of a change in the structureand or its constituent materials. There are many possible techniques foranalyzing a change in response (e.g., due to compression, or due toflexure, etc.), some of which techniques are shown and described aspertains to FIG. 19B1.

FIG. 19B1 shows a depiction 19B00 of columns containing the split ringresonator, or plurality of split ring resonators, and an equation formeasuring the change within the structural members, in accordance withone embodiment. As an option, the depiction 19B00 may be implemented inthe context of any one or more of the embodiments set forth in anyprevious and/or subsequent figure(s) and/or description thereof. Ofcourse, however, the depiction 19B00 may be implemented in the contextof any desired environment. Further, the aforementioned definitions mayequally apply to the description below.

As shown, the depiction 19B00 shows cured columns containing a splitring resonator, or plurality of split ring resonators 1904, and variousequations for measuring the change within the structural members.Additionally, a change in the compression 1916 of the materialssurrounding the split ring resonators 1904 initiates a change inresponse 1922 from the split ring resonators (as shown in FIG. 19B2).Further, FIG. 19B1 shows an example equation for measuring the degree ofcompression within the structural members (as a function of change incompression) Eq. 6. Additionally, although Eq. 6 is shown relating tocompression, and Eq. 7 (hereinbelow) is shown relating to change inresponse, it is to be appreciated that any change torsion, hygrometry(humidity), flexion, response, material property, etc. may be the basisfor determining and/or measuring a change of the split ringresonator(s).

In one embodiment, one use model may support structural assessment of aninfrastructure's concrete foundation (e.g., apartment complex,condominiums, homes, hotels). Additionally, a one use model may supportstructural assessment of a building's infrastructure in general,including monitoring of steel beams, support columns/pillars, and otheraspects of structural health monitoring. Ongoing or periodic monitoringof the integrity of the material over time can indicate whether or notthe material that forms the structure has been altered, for example dueto aging, excessive or related stresses, and/or due to physical damage,etc. In some cases, it may be possible to prevent imminent failure ofthe materials so as to avoid a catastrophe. In some situations, multiplestructural members can combine into one load-bearing structure, theentirety of which load-bearing structure is to be monitored over time.Calibration and periodic monitoring could be accomplished, for example,in a two-step fashion. In a first step, a technician operating a signalgenerator (or similar tool), tunes the signal generator to a selectedfrequency and emits a signal proximal to the split ring resonators in astructural member. A return signal and/or its characteristics (e.g.,attenuation, single frequency resonance, multiple frequency resonance,etc.) from the split ring resonators is captured. The technician storesthe return signal and/or its characteristics as a calibration pointpertaining to a ping of that location and at that given point in time.The return signal and/or its characteristics is later used as acalibration signature corresponding to the point in time when thematerial is deemed to have a baseline state of structural integrity.

In a second step, carried out at any later time after the first step,the technician may repeat the pinging and signature capturing process togather then-current data returned by the split ring resonators in thestructural member. A comparison between the calibration signature andthe then-current data may potentially be indicative of changes in theintegrity of the material. In one embodiment, a change in response 1918might be merely indicative of a change in compression. Certain ranges ofchanges of compression over time may be considered to be normal, and mayoccur in normal use (e.g., as the structure flexes under stresses fromEarth movements such as earth tremors). In addition to the foregoingtechnique for measuring changes in compression, further techniques arepresented hereunder as pertains to measuring changes in flexure.

FIG. 19B2 shows a depiction 19B02 of columns containing the split ringresonator, or plurality of split ring resonators, and an equation formeasuring the change within the structural members, in accordance withone embodiment. As an option, the depiction 19B02 may be implemented inthe context of any one or more of the embodiments set forth in anyprevious and/or subsequent figure(s) and/or description thereof. Ofcourse, however, the depiction 19B02 may be implemented in the contextof any desired environment. Further, the aforementioned definitions mayequally apply to the description below.

In one embodiment, the depiction 19B02 shows a cured slab containing thesplit ring resonator, or plurality of split ring resonators 1904, and anexample equation for measuring the degree of flexion within thestructural members (as a function of change in flexion) Eq. 7.Additionally, a change in the flexion 1920 of the materials surroundingthe split ring resonators 1904 causes a change in response 1922 from thesplit ring resonators resulting in a differing signal response thaninitially determined. This information is deemed imperative formonitoring the integrity of the material in its application.

As previously mentioned in the given case, a split ring resonator orsplit ring resonators 1904 would be implemented in the concretefoundation to allow for monitoring of material. This could beaccomplished, as an example, in a two-step fashion. In a first step, atechnician operating a signal generator (or similar tool), tunes thesignal generator to a selected frequency, which may emit a signalproximal to the split ring resonators in a structural member. A returnsignal and/or its characteristics (e.g., attenuation, single frequencyresonance, multiple frequency resonance, etc.) from the split ringresonators is captured. The technician stores the return signal and/orits characteristics as a calibration point pertaining to a ping of thatlocation and at that given point in time. The return signal and/or itscharacteristics is later used as a calibration signature correspondingto the point in time when the material is deemed to have a baselinestate of structural integrity.

When implementing the split ring resonator or split ring resonators intothe member, the exact orientation and location may not be controllableduring the pour, however the foregoing two-step procedure can still beused. This is because, when pinging the plurality of split ringresonators, an ensemble effect signal (the return from the multiplesplit ring resonators) can be used as a calibration. Again, in thesecond step, carried out at any later time after the first step, thetechnician would repeat the pinging and signature capturing process togather then current data returned by the split ring resonators in thestructural member. A comparison between the calibration signature andthe then-current data may potentially be indicative of changes in theintegrity of the material. On the one hand, a change in response 1918might be merely indicative of a change in compression. Certain ranges ofchanges of compression over time may be considered to be normal, and mayoccur in normal use (e.g., as the structure flexes under stresses fromearth movements such as earth tremors). In addition to the foregoingtechnique for measuring changes in compression, further techniques arepresented hereunder as pertains to measuring changes in flexure.

If the structural member is already in a given use, a split ringresonator or plurality of split ring resonators 1904 can still beimplemented on the structural member, regardless of physicalcharacteristics (e.g. shape, size, location). Examples of such are shownand described as pertains to FIG. 20 .

FIG. 20 illustrates the utilization 2000 of split ring resonatorsexternally on structural members varying in shapes that already in use,in accordance with one embodiment. As an option, the utilization 2000may be implemented in the context of any one or more of the embodimentsset forth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the utilization 2000 may be implemented inthe context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

In one embodiment, FIG. 20 also displays examples of possible factorsand equations that may be vital in determining the size, orientation,location, and application of the split ring resonator or split ringresonators on the structural member. Additionally, FIG. 20 illustratesthe utilization of split ring resonators that are applied externally tostructural members of varying shapes. FIG. 20 displays examples ofpossible factors and equations that may be vital in determining thesize, orientation, location, and application of the split ring resonatoror split ring resonators on the structural member.

More specifically, FIG. 20 depicts a horizontal member 2002 where thesplit ring resonator 1904 can be attached (e.g., using ultrasonicwelding) and used in a given application (e.g., an axle component, a tierod component, a push rod, rebar, etc.). In addition to the horizontalelongated members, the split ring resonator could also be attached to acurved member 2004 (e.g., bucket handle, suspension part, a portion ofspring, rebar, etc.).

In one specific case, a split ring resonator 1904 or a plurality ofspaced split ring resonators can be applied to rebar using any knowntechnique, after which the rebar may be situated into a form. When theconcrete or other construction composition is poured into the form, thejuxtaposition of the split ring resonators on the rebar and thejuxtaposition of the split ring resonators in the form remainssubstantially the same as when the split ring resonators were applied tothe rebar and situated in the form. As such, the split ring resonatorscan be positioned so as to be substantially aligned into ahorizontally-oriented plane (e.g., in an ‘X’ direction), or so as to besubstantially aligned into a vertically-oriented plane (e.g., in a ‘Y’direction), or so as to be substantially aligned into a depth-orientedplane (e.g., in an ‘Z’ direction).

Additionally, or alternatively, a split ring resonator could be attachedto a flat structural member 2006 (e.g., the hood of a car). In thisgiven application the split ring resonator could be used in order tomeasure the flex of a hood of a car dynamically, and at any given momentin time. This method has many advances as compared to the use of a windtunnel in order to measure the flex of the hood of the car. This isbecause, in the wind tunnel case, the vehicle is stationary, whereas inthe contemplated use model where the vehicle is actually underway,actual real time responses can be calculated. Thus, the split ringresonator or split ring resonators 1904 provide instant feedback duringactual driving conditions.

The determined size of the split ring resonator or split ring resonatorsfor each of the structural members may be dependent on the size of themember as well as the application. This is shown by Eq. 8. Specifically,different sizes of the split ring resonator or split ring resonatorsresonate at correspondingly different frequencies. The different sizescan be accounted for during the initial calibration test.

In certain situations (e.g., when applying a split ring resonator to astraight horizontal member, or when applying a split ring resonator to acurved member, or when applying a split ring resonator to a flat member)the optimal location (Eq. 10) and/or orientation (Eq. 9) can bedetermined or inferred from analysis of a finite element model (e.g.,using CAD software such as SOLIDWORKS, AGROS2D, CALCILIX). Morespecifically, the results from the finite element analysis will yieldflexure vectors, compression vectors, and expansion vectors dependingupon the application and desired properties that are of interest. Basedon the results from the finite element analysis, a particular structuralmember can be configured with the split ring resonator at acorresponding location (Eq. 10) and/or orientation (Eq. 9).

FIG. 21 is a flow chart 2100 representing the process in which the splitring resonator is implemented in the given applications, in accordancewith one embodiment. As an option, the flow chart 2100 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the flow chart 2100 may be implemented inthe context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the first step of the process is to determine whether thescenario admits either an internal or external disposition of the splitring resonators (step 2102). In the event of an internal application(step 2104) of the split ring resonator or split ring resonators, themix-in technique would need to be determined (step 2106). In oneembodiment, the split ring resonator or split ring resonators may becombined with an aggregate mixture or cement. The aggregate mixture orcement may then be poured into a structure or foundation and the splitring resonators would disperse randomly throughout the mixtureultimately forming the member (step 2110).

Once the foundation or structure has cured the split ring resonators canbe calibrated, and an initial state or calibration signature can begathered (step 2114). To achieve the calibration signature a uniquesignal may used to ping a response from the split ring resonators. Basedupon the characteristics of the medium in which the split ringresonators are immersed, a response as a function of the medium'sparameters (compression, density, frequency, etc.) may be generated.This initial reading when the structure is in some initial state maybecome the calibration signature and reference parameter for futurecomparisons. Of course, it is to be appreciated that the initial readingmay be reset (and/or recalibrated) at a later point of time (such asrecasting of cement, seismic upgrades, etc.).

In the event of an external application (e.g., via ultrasonic welding)the split ring resonator or split ring resonators would be integratedonto a component in a fashion that would not compromise the accuracy ofthe split ring resonator. The orientation, location, and application ofthe split ring resonator can be used to gather correct data from thesplit ring resonator (step 2108) (for example, the installment of asplit ring resonator to a motor vehicle axle). The orientation of thesplit ring resonator to the axle can be used to achieve a normal,horizontal, or angled vector from the plane of the split ring resonatorwhich does not compromise the signal to noise ratio and allows foroperable return of calibration signature or point. The location of thesplit ring resonator on the axle may be placed in zones of failure andfluctuating stress for appropriate monitoring of the integrity of theaxle. Sonic welding of the split ring resonators (step 2112) to the axlemay be employed to ensure accuracy of the split ring resonatorscalibration signature and points. Sonic welding which allows fordissimilar materials to bind does not use solder or other materials toform a weld that could dampen or alter the response of the split ringresonators. Of course, it is to be appreciated that any type of affixingmay also be used in lieu of welding.

As shown in the flowchart, both external and internal processes convergeto test event (step 2116). During the test event a stimulus is applied(step 2118) and a response is measured (step 2120). The test event isused to gather and compare calibration points against the calibrationsignature (step 2122). After a given amount of time has elapsed and,strictly as example, a stressful event to the structure or component hastaken place, or routine maintenance check, or a visual observation ofthe component or structure renders need for testing a test is performed.This test returns calibration points which may be similar in nature tocalibration signatures taken later when the structure or component maydiffer in the structure's integrity. A two-step technique could be usedto accomplish obtaining the necessary calibrations. In a first step(step 2120), a technician operating a signal generator (or similartool), tunes the signal generator to a selected frequency, and emits asignal proximal to the split ring resonators in a structural member. Areturn signal and/or its characteristics (e.g., attenuation, singlefrequency resonance, multiple frequency resonance, etc.) from the splitring resonators is captured. The technician stores the return signaland/or its characteristics as a calibration point pertaining to a pingof that location and at that given point in time. The return signaland/or its characteristics is later used as a calibration signaturecorresponding to the point in time when the material is deemed to have abaseline state of structural integrity.

In a second step (step 2122), carried out at any later time after thefirst step, the technician would repeat the pinging and signaturecapturing process to gather then current data returned by the split ringresonators in the structural member. A comparison between thecalibration signature and the then-current data may potentially beindicative of changes in the integrity of the material. On the otherhand, a change in response 1918 might be merely indicative of a changein compression. Certain ranges of changes of compression over time maybe considered to be normal, and may occur in normal use (e.g., as thestructure flexes under stresses from earth movements such as earthtremors. In addition to the foregoing technique for measuring changes incompression, further techniques are presented hereunder as pertains tomeasuring changes in flexure. Regardless of the shape of the member thepreviously technique, or any related technique disclosed herein, can beused to gather the necessary information.

The calibration points are then compared against the calibrationsignature. If the difference of the two signals is outside of theacceptable error threshold or tolerance (the “Yes” option of decision2124) then the “YES” branch of decision 2124 is taken and a report ismade (step 2126). Additionally, FIGS. 22A1-22A3 illustrates otherembodiments where the aforementioned is applied.

FIGS. 22A1 through 22A3 are being presented to illustrate use of splitring resonators or a plurality of split ring resonators within roadsidebarriers, in accordance with one embodiment. As an option, the FIGS.22A1 through 22A3 may be implemented in the context of any one or moreof the embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the FIGS. 22A1 through22A3 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, FIG. 22A1 depicts a roadway 2202 containing a concrete barrier2206 and/or metal barrier 2204, or possibly both, that use a split ringresonator or a plurality of split ring resonators. Roadside barriers aremeant to reduce the severity of potential vehicle accidents (e.g., goingover a cliff, into a body of water, etc.) by absorbing the force from anoncoming car and stopping the car from continuing on its path byallowing the body of the barrier to deform in its shape. After this hasbeen accomplished, the integrity of the material of the barrier may bealtered and possibly may need to be replaced due to the deformation ofthe material. Even if the outside physical aspect of the barrier seemsto be unaltered, there may be deformities within the material causing itto have weakened as a result of the impact, thus requiring the barrierto be replaced.

To determine when and how often the given barrier may need to bereplaced, split ring resonators may be placed within the concretebarriers as shown in FIG. 22A2 (e.g., an example of the techniquedepicted in FIG. 19A). Once the foundation or structure has cured, thesplit ring resonators can be calibrated, and an initial state orcalibration signature can be gathered, for example, by a two-stepfashion technique. In a first step, a technician operating a signalgenerator (or similar tool), tunes the signal generator to a selectedfrequency, and emits a signal proximal to the split ring resonators inthe concrete barrier. A return signal and/or its characteristics (e.g.,attenuation, single frequency resonance, multiple frequency resonance,etc.) from the split ring resonators is captured. The technician storesthe return signal and/or its characteristics as a calibration pointpertaining to a ping of that location and at that given point in time.The return signal and/or its characteristics is later used as acalibration signature corresponding to the point in time when thematerial is deemed to have a baseline state of structural integrity.

The same can be applied to a metal barrier represented in FIG. 22A3. Thesplit ring resonators may also be attached with an application technique(e.g., ultrasonic welding) of step 2112. Once attached to the metalbarrier, the split ring resonators can be calibrated, and an initialstate or calibration signature can be gathered using the previouslytwo-step technique. Similarly, a racetrack barrier can also use aplurality of split ring resonators to monitor the integrity of thebarrier which is depicted in FIG. 22B.

Of course, it is to be appreciated that split ring resonators may beembedded in other materials (other than concrete barriers of FIG. 22A2and/or metal barriers of FIG. 22A3), including but not limited to:aviation related embodiments (e.g., wings, landing gear, planecomponent, etc.), nautical related embodiments (e.g., sails, masts,buoys, structural steel, etc.), utilities related embodiments (e.g.,power line structure, transmission line, delivery pipelines, etc.),construction related embodiments (e.g., beams, concrete pylons, etc.),biomedical related embodiments (e.g., prosthetics, implants, orthotics,etc.), professional sports equipment related embodiments (e.g., helmets,protective pads, hand-held implements, footwear, etc.), forging orsmelting related embodiments (e.g., metals, composites, alloys, etc.),power production related embodiments (e.g., solar arrays, hydroelectricdams, wind-powered turbines, natural gas housing and transport, etc.),automobile related safety and/or performance embodiments (e.g., engineperformance, suspension, chassis and body integrity, etc.),manufacturing related embodiments (e.g., assembly, 3D printing,component amalgamation, testing, etc.), agriculture related embodiments(e.g., growth rates, temperature control, moisture saturation,ultraviolet light exposure, etc.), and/or space travel relatedembodiments (e.g., air lock performance, propellant receptacleintegrity, launch effect tolerance measurements, capsule/fuselagedistortion during flight, etc.). In short, use of split ring resonatorsfor determining deformation of the material to which it is affixed or inwhich it is incorporated may relate to any application where it can beimbedded and/or affixed, where the substrate to which it is affixed orin which it is embedded is of a sufficient permanent state that anydeformation of the substrate would be an indication of material fatigue.

With respect to one specific example, drilling rigs are often exposed tohigh temperature and corrosive environments for offshore application.Such conditions often cause drillpipe failures, which resultpredominately from metal fatigue. Having split ring resonators embedded,in one embodiment, within the drillpipe itself, would allow metalfatigue to be detected in advance of causing a drillpipe failure (andthe inherent complications that arise from such failure). Consistentwith the description herein, the split ring resonators embedded in thedrillpipe may be initially calibrated, where an initial state orcalibration signature can be gathered (consistent with the two-stepfashion technique). A signal generator (or similar tool) may tune thesignal generator to a selected frequency, and emit a signal next to thesplit ring resonators in the drillpipe. A return signal and/or itscharacteristics may be captured, which in turn, may be stored as acalibration signature of the material at that state in time. At a latertime period (consistent with step 2116), a stimulus may be applied (perstep 2118) and a response may be measured (per step 2120), which in turnmay be compared to the calibration signature (per step 2122). It is tobe appreciated that the stimulus may be applied at any time period rate(e.g. every minute, day, week, month, etc.) as predetermined by a user.In this manner, deformation (which may be indicated of fatigue crack,crack propagation, etc.) may be measured within the drillpipe, anddetected before actually causing a drillpipe failure.

FIG. 22B depicts a roadside barrier 22B00 used in a racetrack showingstructural components that constitute the roadside barrier in which asplit ring resonator or split ring resonators can be placed, inaccordance with one embodiment. As an option, the roadside barrier 22B00may be implemented in the context of any one or more of the embodimentsset forth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the roadside barrier 22B00 may beimplemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

In one embodiment, the roadside barrier 22B00 may include a steel andfoam energy reduction barrier. As shown, the racetrack is to the side ofthe foam absorbers (with internal split ring resonators 2208). Steel andfoam energy reduction barriers may be used in the high speed section ofcertain tracks and work by absorbing the kinetic energy during impact toreduce severity of accidents as well as to separate the spectating crowdfrom possible hazards in the case of a collision of cars and/or toprevent hazardous material from being launched into the crowd. When thebarrier contacts the car or cars, the absorbed energy travels along thesides of the wall reducing the damage to the cars and preventing injuryto the spectators.

Additionally, an array of split ring resonators 2212 can be placedeither on the surface and/or internally on the putter steel barrier 2210in order to obtain needed information to determine the integrity of thebarrier after, for example, one or more collisions, or to determine theintegrity of the barrier over a certain period of time. In exemplarycases, the array of split ring resonators 2212 can be placed in thefront and back of the putter steel barriers, and/or embedded in foamabsorbers and/or on or in any of the cement walls.

In one specific embodiment, after the array of split ring resonators2212 has been disposed (e.g., placed in the foam absorbers with internalsplit ring resonators 2208 and/or externally or internally placed in theputter steel barrier 2210, and/or externally or internally placed in thefoam absorbers, etc.), they can be calibrated by way of the two-steptechnique detailed herein.

In a first step, a technician operating a signal generator (or similartool), tunes the signal generator to a selected frequency, which emits asignal proximal to the split ring resonators in the foam absorbers withinternal or external split ring resonators 2008 and/or externally orinternally in the putter steel barrier 2210. A return signal and/or itscharacteristics (e.g., attenuation, single frequency resonance, multiplefrequency resonance, etc.) from the split ring resonators is captured.The technician stores the return signal and/or its characteristics as acalibration point pertaining to a ping of that location and at thatgiven point in time. The return signal and/or its characteristics islater used as a calibration signature corresponding to the point in timewhen the material is deemed to have a baseline state of structuralintegrity.

In a second step, carried out at any later time after the first step,the technician would repeat the pinging and signature capturing processto gather the then-current data returned by the split ring resonators inthe structural member. A comparison between the calibration signatureand the then-current data may potentially be indicative of changes inthe integrity of the material. On the other hand, a change in response1918 might be merely indicative of a change in compression. Certainranges of changes of compression over time may be considered to benormal, and may occur in normal use (e.g., as the structure flexes understresses from earth movements such as earth tremors. In addition to theforegoing technique for measuring changes in compression, furthertechniques are presented hereunder as pertains to measuring changes inflexure. After analysis of the gathered data, a report can beconstructed in which replacement of the barriers can be determined.

FIG. 23 shows a depiction 2300 of split ring resonators disposed on thesurface of a concrete structure after the concrete has been poured intoa given structural form, in accordance with one embodiment. As anoption, the depiction 2300 may be implemented in the context of any oneor more of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the depiction2300 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, the depiction 2300 includes split ring resonators (e.g., splitring resonator 19041, split ring resonator 19042, split ring resonator19043) disposed on the surface of a concrete structure (e.g., column orwall 1908) after the concrete has been poured into a given structuralform. Placement of such split ring resonators (e.g., the shownsurface-applied split ring resonators 2302) can be done as a “retrofit”,in some cases long after the pour has cured, and in some cases longafter a building has been erected using columns and/or walls. Theconstruction, placement of, and means of affixing surface-applied splitring resonators 2302 to a structure can be accomplished using any knowntechnique. For example, such surface-applied split ring resonators 2302can be printed or silk-screened onto a substrate in a roll, and thatroll of substrate or portions thereof can be applied, possibly with anadhesive to a surface of a column or wall. In some cases, the substrateis lifted off, leaving the surface-applied split ring resonators 2302affixed to the surfaces of the column or wall. In some cases, thesurface-applied split ring resonators 2302 can be printed directly ontothe rebar. In some cases, the surface-applied split ring resonators 2302can be printed onto a substrate using a inkjet or bubble jet printer. Insome cases, the surface-applied split ring resonators 2302 can beprinted onto a substrate using offset or printing (e.g., multi-coloroffset printing). In some cases, the surface-applied split ringresonators 2302 can be printed onto a substrate using gravure printingtechniques.

A calibration and test module 2301 can be situated proximal to anylocation where there are surface-applied split ring resonators 2302. Oneor more calibration signatures based on a particular combination ofoccurrences of emitted RF signals 210 and corresponding occurrences ofreturned RF signals 212 can be communicated over a network to upstreamcomponents 113. Strictly as examples that are pertinent to this andother embodiments, an upstream component may include, but not be limitedto, modules that perform continual inspection and analysis of thestructures, modules that combine to serve in the capacity of an earlywarning system, modules that comport with governance, and/or modulesthat comport with any regulatory reporting requirements.

Any of the foregoing techniques for making and using split ringresonators can be combined. For example, surface-applied split ringresonators can be retrofitted onto surfaces of a roadside barriersand/or components thereof. Additionally, for example, the upstreamcomponents might include a racetrack safety monitoring unit. Further,split ring resonators of a first geometry of split ring resonators(e.g., concentric rings) can be combined (e.g., proximally-juxtaposed)with split ring resonators of a second geometry (e.g., concentriccylinders). Strictly as yet another embodiment, a roadside barrier madeof steel and/or other barrier components made of steel of anotherelectrically-conducting material can serve as an electrically-conductivelayer that is dielectrically separated (e.g., via an adhesive) from anyone or more split ring resonators that are disposed onto the surface ofthe roadside barrier.

The foregoing discloses various ways to incorporate or otherwise embedsplit ring resonators into the base materials that form the intendedstructural member (e.g., such as in cement pours). Further, theforegoing discloses various ways to affix split ring resonators onto asurface of a structural member (e.g., such as a tie-rod of a steeringmechanism in an automobile). It is additionally envisioned to use a RF“horn” to emit a particular signal and measure the response of theembedded split ring resonators, as discussed herein as well.

Some methods include disposing split ring resonators onto a (possiblyprinted) “ground plane” which forms an assembly that is in turn appliedonto a surface of the structural member. This greatly may increasesensitivity of the split ring resonator over a broad range of EM.

The foregoing methods support static non-destructive testing merely bycomparing a current response/signature to a previously-taken calibrationresponse/signature and then classifying the differences between the twosignatures. More particularly, certain differences that are apparentbetween the signatures can be correlated to corresponding physicalproperty changes. In some cases, the physical property changes areindicative of aging (e.g., brittle-ization). In some cases, the physicalproperty changes are indicative of stretching, compression, otherdeformation, etc.

In some cases, the physical property changes are indicative ofdynamically changing property changes (e.g., vibration). Capturing aseries of a dynamically-taken series of responses/signatures to apreviously-taken series of calibration responses/signatures supportsdynamic non-destructive testing. Difference that are apparent betweenthe two sets signatures can be correlated to physical property changessuch as cyclical deformations. In some cases, the physical propertychanges are indicative of aging (e.g., changes in the elasticdeformation curve). In some cases, the physical property changes thatoccur between readings and/or the physical property changes that aremeasured when comparing one series of readings to another series ofreadings can be indicative of elastic versus plastic deformations, whichare sometimes indicative of imminent failure. Strictly as one example,imminent failure of a component might be indicated when a measuredelasticity curve (e.g., based on a series of readings) resembles aregion of an elasticity curve that has been designated as preceding afailure event.

FIG. 24A depicts a sensing laminate 24A00 including alternating layersof carbon-containing resin and carbon fiber in contact with one-another,in accordance with one embodiment. As an option, the sensing laminate24A00 may be implemented in the context of any one or more of theembodiments set forth in any previous and/or subsequent figure(s) and/ordescription thereof. Of course, however, the sensing laminate 24A00 maybe implemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

As shown, the sensing laminate 24A00 includes a schematic side-viewcutaway diagram composed of multiple layers disposed on each other,including (sequentially) a carbon-containing resin 24042, a carbon fiber24022, a carbon-containing resin 24041, and a carbon fiber 24021. In oneembodiment, the sensing laminate 24A00 can be representative of anysensor discussed with relation to that shown in FIGS. 24A-24C. The term“resin” (in polymer chemistry and materials science), generally, refersto a solid or highly viscous substance of plant or synthetic origin thatis typically convertible into polymers (a large molecule, ormacromolecule, composed of many repeated subunits). Synthetic resins maybe industrially produced resins, typically viscous substances thatconvert into rigid polymers by the process of curing. In order toundergo curing, resins typically contain reactive end groups, such asacrylates or epoxides. The term “carbon fiber”, refers to fibers about5-10 micrometers (μm) in diameter and composed mostly of carbon atoms.Carbon fibers have several advantages including high stiffness, hightensile strength, low weight, high chemical resistance, high temperaturetolerance and low thermal expansion.

Any one or more of the carbon-containing resin 24042, the carbon fiber24022, the carbon-containing resin 24041, and the carbon fiber 24021 canbe tuned to demonstrate or exhibit one or more specific resonancefrequencies upon being pinged by RF signals by incorporating specificconcentration levels of the any one or more of the aforementionedcarbon-containing microstructures. The sensing laminate can include anyconfiguration, orientation, order, or layering of any one or more of thecarbon-containing resin 24042, the carbon fiber 24022, thecarbon-containing resin 24041, and the carbon fiber 24021 and/or feweror additional layers comprising similar or dissimilar materials.Additional layers of resin can be layered interstitially betweenadditional layers of carbon fiber.

Each layer of carbon-containing resin can be formulated differently toresonate at a different expected or desired tuned frequency. Thephysical phenomenon of material resonation can be described with respectto a corresponding molecular composition. For example, a layer having afirst defined structure, such as a first molecular structure willresonate at a first frequency, whereas a layer having a second,different molecular structure can resonate at a second, differentfrequency.

Material having a particular molecular structure and contained in alayer will resonate at a first tuned frequency when that layer is in alow energy state, and will resonate at a second different frequency whenthe material in the layer is in an induced higher-energy state. Forexample, material in a layer that exhibits a particular molecularstructure can be tuned to resonate at a 3 GHz when the layer is in anatural, undeformed, low energy state. In contrast, that same layer canresonate at 2.95 GHz when the layer is at least partially deformed fromits natural, undeformed, low energy state. As a result, this phenomenoncan be adjusted to accommodate the needs for detecting, with a highdegree of fidelity and accuracy, even the most minute aberration to, forexample, a tire surface contacting against a road surface such aspavement and experiencing enhanced wear at a certain localized region ofcontact. Race cars racing on demanding race circuits (referring tohighly technical, windy tracks featuring tight turns and rapidelevational changes) can benefit from such localized tire wear ordegradation information to make informed tire-replacement decisions,even in time-sensitive race-day conditions. As described herein, thephenomenon may be applied to any context and/or application where splitring resonators can be integrated within or affixed to a substrate.

FIGS. 24B1 and 24B2 depict a frequency-shifting phenomenon asdemonstrated by a sensing laminate including carbon-containing tuned RFresonance materials, in accordance with one embodiment. As an option,the FIGS. 24B1 and 24B2 may be implemented in the context of any one ormore of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the FIGS. 24B1and 24B2 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

The frequency-shifting phenomenon referred to above (with respect toFIG. 24A, such as transitioning from resonating at a frequency of 3 GHzto 2.95 GHz) is shown and discussed with reference to FIGS. 24B1-24B2.FIG. 24B2 depicts a frequency-shifting phenomenon as exhibited in asensing laminate that includes carbon-containing tuned resonancematerials.

As generally understood, atoms emit electromagnetic radiation at anatural frequency for a given element. That is, an atom of a particularelement has a natural frequency that corresponds to characteristics ofthe atom. For example, when a Cesium atom is stimulated, a valenceelectron jumps from a lower energy state (such as, a ground state) to ahigher energy state (such as, an excited energy state). When theelectron returns to its lower energy state, it emits electromagneticradiation in the form of a photon. For Cesium, the photon emitted is inthe microwave frequency range; at 9.192631770 THz. Structures that arelarger than atoms, such as molecules formed of multiple atoms alsoresonate (such as by emitting electromagnetic radiation) at predictablefrequencies. For example, liquid water in bulk resonates at 109.6 THz.Water that is in tension (such as, at the surface of bulk, in variousstates of surface tension) resonates at 112.6 THz. Carbon atoms andcarbon structures also exhibit natural frequencies that are dependent onthe structure. For example, the natural resonant frequency of a carbonnanotube (CNT) is dependent on the tube diameter and length of the CNT.Growing a CNT under controlled conditions to control the tube diameterand length leads to controlling the structure's natural resonantfrequency. According, synthesizing or otherwise “growing” CNTs is oneway to tune to a desired resonant frequency.

Other structures formed of carbon can be formed under controlledconditions. Such structures include but are not limited to carbonnano-onions (CNOs), carbon lattices, graphene, carbon-containingaggregates or agglomerates, graphene-based, other carbon containingmaterials, engineered nanoscale structures, etc. and/or combinationsthereof, any one or of which being incorporated into sensors of vehiclecomponents according to the presently disclosed implementations. Suchstructures can be formed to resonate at a particular tuned frequencyand/or such structures can be modified in post-processing to obtain adesired characteristic or property. For example, a desired property suchas a high reinforcement value can be brought about by selection andratios of combinations of materials and/or by the addition of othermaterials. Moreover, co-location of multiples of such structuresintroduces further resonance effects. For example, two sheets ofgraphene may resonate between themselves at a frequency that isdependent on the length, width, spacing, shape of the spacing and/orother physical characteristics of the sheets and/or their juxtapositionto each other.

As is known in the art, materials have specific, measurablecharacteristics. This is true for naturally occurring materials as wellas for engineered carbon allotropes. Such engineered carbon allotropescan be tuned to exhibit physical characteristics. For example, carbonallotropes can be engineered to exhibit physical characteristicscorresponding to: (a) a particular configuration of constituent primaryparticles; (b) formation of aggregates; and (c) formation ofagglomerates. Each of these physical characteristics influence theparticular resonant frequencies of materials formed using correspondingparticular carbon allotropes.

In addition to tuning a particular carbon-based structure for aparticular physical configuration that corresponds to a particularresonant frequency, carbon-containing compounds can be tuned to aparticular resonant frequency (or set of resonant frequencies). A set ofresonant frequencies is termed a resonance profile.

FIG. 24B1 depicts a first carbon-containing structure that resonates ata first frequency, which can be correlated to an equivalent electricalcircuit comprising a capacitor C₁ and an inductor L₁ (note that thecontext of Eq. 3, provided below, can also be found hereinabove withrespect to FIG. 2 , and/or the carbon-containing structures of FIGS.18A-18Y, in particular). The frequency f₁ is given by the equation:

$\begin{matrix}{f_{1} = \frac{1}{2\pi\sqrt{L_{1}C_{1}}}} & \left( {{Eq}.3} \right)\end{matrix}$

FIG. 24B2 depicts a slight deformation of the same firstcarbon-containing structure of FIG. 24B1. The deformation causes achange to the physical structure, which in turn, changes the inductanceand/or capacitance of the structure. The changes can be correlated to anequivalent electrical circuit comprising a capacitor C₂ and an inductorL₂. The frequency f₂ may given by the equation:

$\begin{matrix}{f_{2} = \frac{1}{2\pi\sqrt{L_{2}C_{2}}}} & \left( {{Eq}.4} \right)\end{matrix}$

FIG. 24B3 is a graph 24B300 depicting idealized changes in RF resonanceas a function of deflection, in accordance with one embodiment. As anoption, the graph 24B300 may be implemented in the context of any one ormore of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the graph24B300 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, the graph 24B300 depicts idealized changes in measuredresonance as a function of deflection. As an option, one or morevariations of graph 24B300 or any aspect thereof may be implemented inthe context of the implementations described herein. The graph 24B300(or any aspect thereof) may be implemented in any environment.

The implementation shown in FIG. 24B3 is merely one example. The showngraph depicts one aspect of deformation, specifically deflection. As amember or surface undergoes deformation by deflection (such as curving),the deformation can change the demonstrated resonance frequency of themember upon being pinged by a signal, such as an RF signal. The shape ofthe curve can depend on characteristics of the member, such as oncharacteristics of the laminate that forms the member or surface. Thecurve can be steep at small variations, whereas the curve flattens asthe deflection reaches a maximum. Moreover, the shape of the curvedepends in part on the number of layers of the laminate, the geometry ofthe carbon structures, how the carbon is bonded into the laminate, etc.

FIG. 24B4 is a graph 24B400 depicting changes in RF resonance for4-layer and 5-layer laminates, in accordance with one embodiment. As anoption, the graph 24B400 may be implemented in the context of any one ormore of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the graph24B400 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, the graph 24B400 depicts changes in resonance for 4-layerlaminates 292 and for 5-layer laminates 294. As an option, one or morevariations of graph 24B400 or any aspect thereof can be implemented inthe materials and systems described herein. Materials such as thedescribed laminates can be deployed into many applications. Oneparticular application may be for surface sensors, which can be deployedinto, on, or over many locations throughout a vehicle. An example ofsuch deployments may be shown and described as pertains to FIG. 24C.

FIG. 24C depicts surface sensor deployments in areas of a vehicle 24C00,in accordance with one embodiment. As an option, the vehicle 24C00 maybe implemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the vehicle 24C00 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the vehicle 24C00 shows example surface sensor deployments inselected locations of a vehicle. Such example surface sensordeployments, or any aspect thereof, may be implemented in or on avehicle exposed to any possible exterior environmental condition, suchas snow, sleet, hail, etc.

Tuned resonance sensing carbon-containing materials can be incorporatedinto or with automotive features, surfaces, and/or components in thecontext of durable sensors in various exterior surfaces of vehicles. Asshown, the vehicle is equipped with surface sensors on the front faring(such as, hood) of the vehicle, on support members of the vehicle, andon the roof of the vehicle. Each of the foregoing locations of thevehicle can be subjected to stresses and accompanying deformationsduring operation of the vehicle. As examples, the surface sensors on thefront faring will undergo air pressure changes when the vehicle is inoperation (such as, during forward motion). Under the forces of the airpressure, the material that composes the surface can deform slightlyand, in accordance with the phenomenon described as pertains to FIG.24B1 and FIG. 24B2, demonstrate a change in resonant frequency of thematerial proportionate to the degree of change or deformation of thematerial. Such a change can be detected using the ‘ping” and observationtechniques described earlier.

Observed emitted signals can collectively define a signature for aparticular material or surface and can be further classified. Specificcharacteristics of the signal can be isolated for comparison andmeasurement to determine calibration points that correspond to thespecific isolated characteristics. Accordingly, aspects of theenvironment surrounding a vehicle can be accurately and reliablydetermined.

For example, if the deformation of the surface sensor results in afrequency shift from 3 GHz to 2.95 GHz, the difference can be mapped toa calibration curve, which in turn can yield a value for air pressure. Avehicle component such as a panel, roof, hood, trunk, or airfoilcomponent can provide a relatively large surface area. In such cases,transceiver antennas can be distributed on the observable side of thecomponent. Several transceiver antennas can be distributed into anarray, where each element of the array corresponds to a section of thelarge surface area. Each transceiver antenna can be installed on orwithin the wheel wells of the surface sensor deployments 24C00 as shownand be independently stimulated by pings/chirps. In some cases, eachelement of the array can be stimulated sequentially, whereas, in othercases, each element of the array is stimulated concurrently.Aerodynamics of the vehicle can be measured over large surface areas bysignal processing employed to distinguish signature returns fromproximal array elements.

Signature returns from a particular array element can be analyzed withrespect to other environmental conditions and/or other sensed data. Forexample, deflection of a particular portion of an airfoil componentmight be compared with deflection of a different portion of the airfoilcomponent, which in turn might be analyzed with respect to then-currenttemperatures, and/or then-current tire pressure, and/or any other sensedaspects of the vehicle or its environment. As heretofore described, aresonator circuit (such as is shown in 24B1 and 24B2) can be implementedby situating a resonator in a surface panel of the vehicle (as is shownin 24C). Configurations of other embodiments are specifically tuned tobe able to locate resonators (e.g. Split ring resonators) across thevehicle's surface. An array, or matrix of surface sensors varying insize, can be deployed into or on over many locations throughout avehicle in order for the vehicle's conditions to be analyzed in presenttime. One such deployment may be found, for example, in FIG. 29 ,described hereinbelow.

FIG. 25A provides a depiction 2500 of interaction between a vehicle andsplit ring resonators disposed in roadway asphalt and/or on the surfaceof a road, in accordance with one embodiment. As an option, thedepiction 2500 may be implemented in the context of any one or more ofthe embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the depiction 2500 maybe implemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

As shown, the depiction 2500 may include a vehicle 2502, split ringresonators 2504 located in and/or on a road surface, and road surface tovehicle interaction 2506. In one embodiment, the depiction 2500 may beused to determine tire stiction (and/or rolling friction). For example,maintaining static contact with the road enables control of the vehicle(whereas losing static contract with the road can lead to lost ofcontrol of the vehicle). The split ring resonators 2504 may be used tomeasure tire (and/or interfacial) stiction (as a function of tire treadthickness). The process for determining tire stiction is explained ingreater detail below with reference to FIG. 27 .

FIG. 25B provides a depiction of how split ring resonators disposedwithin or on a tire can be used to measure tire stiction, in accordancewith one embodiment. As an option, the depiction 2500 may be implementedin the context of any one or more of the embodiments set forth in anyprevious and/or subsequent figure(s) and/or description thereof. Ofcourse, however, the depiction 2500 may be implemented in the context ofany desired environment. Further, the aforementioned definitions mayequally apply to the description below.

As shown, the depiction 2501 may include the vehicle 2502, split ringresonators 2503 located in and/or on a tire, and tire interaction 2505.In one embodiment, the depiction 2501 may be used to determine tirestiction (and/or rolling friction). For example, the split ringresonators 2503 located in and/or on a tire may be used to measure tire(and/or interfacial) stiction (as a function of tire tread thickness).

In various embodiments, the split ring resonators 2504 located in and/oron a road surface, and the split ring resonators 2503 located in and/oron a tire may be used to measure a tire's actual stiction to the surfaceof the road, as well as measure a tire's actual thickness on the surfaceof the road. Such measurements may occur in real-time, even while thevehicle 2502 is being operated. In this manner, tire stiction may bemeasured continuously (or near continuously) with high accuracy, giventhe fact that the split ring resonators 2504 and 2503 do not rely onelectronics (which are more prone to failure and other mechanicalissues).

As an example, with the car racing industry, while the vehicle 2502 isbeing driven, split ring resonators (located in and/or on the car, suchas the tire, and/or in and/or on the road) may provide real-time data todrivers and pit crews of real-time permittivity relating to tirestiction. Such real-time data may allow for immediate feedback to howthe tire is responding and interacting with the surface of the road,which in turn, may allow the driver and pit crew to adjust and fine-tunethe vehicle (e.g. tire tread type, power to tires, wind shield, wing,spoiler, etc.) to allow for greater tire stiction (to maximize controland performance of the vehicle, at a minimum). Of course, any otherfine-tuning of the vehicle may be performed to ensure tire stiction.

In one embodiment, the split ring resonators 2504 and 2503 may below-cost sensor due to the fact that it does not rely on electronics forfunction. As such, the split ring resonators 2504 and 2503 may not onlyimprove real-time data gathering (at higher accuracy), but at a lowercost than current alternatives.

FIG. 26 depicts placement 2600 of split ring resonators disposed inroadway asphalt and/or on the surface of a road, in accordance with oneembodiment. As an option, the placement 2600 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the placement 2600 may be implemented in the context of anydesired environment. Further, the aforementioned definitions may equallyapply to the description below.

As shown, the placement 2600 includes a vehicle 2602, split ringresonators 2604, and vehicle interaction 2606. The location of the splitring resonators 2604 (as shown within FIG. 26 ) is arbitrary. The keytake-away of the location of such split ring resonators 2604 is thatthey may be placed anywhere in or on the surface of the road. In oneembodiment, FIG. 26 may apply to a race car track, which may necessitatea greater number of split ring resonators 2604 (for increased datagathering and performance fine-tuning). In contrast, in otherapplications, such as on a normal highway or thoroughfare, the locationof split ring resonators 2604 may be spaced at a greater amount (as finetuning of performance may not be needed).

As discussed herein, the split ring resonators 2604 may be used tocollect data in relation to tire stiction. Such data may be used, inturn, to modify parameters associated with the car. Additionally, suchdata may be used for safety (of the vehicle and/or of the road). Forexample, if the split ring resonators 2604 determined that real-timestiction levels have reduced (indicating a loss of traction), trafficadvisories may immediately alert other drivers of hazardous roadconditions (and likewise decrease the speed limit in and/or around thearea where loss of traction was detected). In this manner, the splitring resonators 2604 may be used for traffic management and/or safety.

Further, split ring resonators, such as those located in and/or a tire(such as the split ring resonators 2503) may be used as an alternativeto conventional anti-lock braking systems (which typically rely on wheelspeed sensors and vehicle speed sensors to determine if the tire hasstopped turning). The split ring resonators 2503 may provide moreaccurate data with less latency (between time of detecting to time ofreporting out to a control module, such as millisecond). Further, onceagain, because the split ring resonators 2503 do not rely on electronicsto function (contrary to conventional sensor systems), they would beless prone to error and failure.

In another embodiment, the split ring resonators 2604 may be used todetermine driver capability and/or track driver performance. Forexample, if an overenthusiastic driver accelerates rapidly, or anaggressive driver brakes forcefully, such data may be used to create adriver profile (of driver performance). For drivers that are training(and need objective data feedback), such data may be used to assist thedriver in training (to learn to drive in a more pleasant manner).Further, such data may be tied to an auto-insurance carrier, wherepreferential rates may be associated with less aggressive drivinghistorical tendencies.

In this manner, the split ring resonators 2604 may be used in a varietyof scenarios and ways such that measuring tire stiction may be used notonly to better control the vehicle (ensure traction between the vehicleand the surface of the road), but based on such data gathered, may beused for safety, driver training, insurance carrier rates, etc.

FIG. 27 is a flow chart 2700 representing the process to determine tirestiction, in accordance with one embodiment. As an option, the flowchart 2700 may be implemented in the context of any one or more of theembodiments set forth in any previous and/or subsequent figure(s) and/ordescription thereof. Of course, however, the flow chart 2700 may beimplemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

As shown, the flow chart 2700 begins with determining tire treadthickness (step 2702). Next, a current measurement is determined (step2704). For example, a current measurement may include a deformation of asplit-ring resonator at the point that the tire meets the road. Suchdeformation may be measured (in the form of a frequency shift), and theensemble effect (things associated with and/or effected by the actioncausing the deformation) may track a permittivity of the surroundings,including but not limited to water, tar, blacktop (asphalt), concrete,etc. If the current measurement is a match with a baseline measurement(per decision 2706), then the method returns back to step 2702 todetermine tire tread thickness, and step 204 to determine refractiveindex. When the refractive index is not a match (per decision 2706),then the method 2700 proceeds to step 2708 and the vehicle is adjustedto achieve a match.

In one embodiment, the refractive index may relate to measuringreflectivity (which may use the refractive index) for each tire layerand determining the permittivity of each tire layer. When the tirestiction is high, the tread thickness (and hence the reflectivity andpermittivity) will increase proportionally. If tire stiction has beenlost (e.g. traction has been lost), a mismatch (e.g. a non proportionalreflectivity and permittivity) will exist with respect to the tire treadthickness. In this manner, tire tread thickness can be used to determinetire stiction as a function of refractive index (and hencereflectivity), and permittivity.

Additionally, a refractive index mismatch in compounded materials(particularly in tires, asphalt, plastics, rubber, metal alloy, etc.)may be used to detect variations of scattering parameters (orS-parameters, elements of a scattering matrix, etc.) for stictionlevels. Such scattering parameters may relate to stimulating (viawireless signals) one or more split ring resonators located in or on atire (or a vehicle, a vehicle component, a surface of a road, etc.).Such one or more split ring resonators may be used to obtain animmediate read of tire tread thickness (which in turn may be used todetermine tire stiction, as described hereinabove).

Further, use of the split ring resonators (as a basis to determine tirestiction) provides a very economical small form factor solution thatdoes not rely on electronics to function. Such factors, therefore, incombination with high accuracy with low latency, make split ringresonators a viable solution for a plethora of applications.

FIG. 28 shows a correlation 2800 between measured frequencies and treadthickness, in accordance with one embodiment. As an option, thecorrelation 2800 may be implemented in the context of any one or more ofthe embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the correlation 2800 maybe implemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

As shown, a tire 2802 includes multiple one or more tire belt plies (ina manner consistent with the tire 1002). The carbon-basedmicrostructures incorporated within the tire 2802 may includes splitring resonators. Such split ring resonators may have a natural resonance(such as approximately 1.0 GHz), and in response to external conditions(such as driving the tire), the tire 2802 may deform and/or otherwise bealtered. The deformation and/or alteration within the tire 2802 may bemeasured (in terms of a response attenuation) as a frequency response ofthe split ring resonators.

The frequency response is shown in model 2804. In one embodiment, themodel 2804 may correlate with impedance spectroscopy energy to and froma tire. Such energy (measured in terms of frequency) may be used todetermine tire stiction. For example, tire thickness of the tire 2802may alter, such as between a natural state and an in-use driving state.During in-use driving state, the tire 2802 may have stiction (andtraction) with the surface of a road. Such a state (of having tirestiction) may be correlated with a matching frequency model (shown, inone example, in the model 2804). However, when tire stiction is lost(e.g. a lost of tire traction occurs), the corresponding model 2804 mayno longer match. For example, when stiction is lost, then permittivitymay decrease rapidly. A calibration of how stiction works underdifferent conditions may allow comparison of then-current readings (andchanges in readings) to be compared to the calibration curves.

In this manner, impedance spectroscopy may be used to measurefrequencies samples of split ring resonators found in or on a tire. Itis to be appreciated that although the correlation 2800 is shown withrespect to one embodiment of a tire, other applications (such as inrelation to car components, car skin, road surface conditions, metalfatigue conditions, construction material, etc.) are envisioned in asimilar manner.

As such, split ring resonators may be disposed in and/or on a material(including internal components such as wiring or external componentssuch as road asphalt) and can be used to provide information pertainingto the material in and/or on which it is located.

FIG. 29 shows a section 2900 of a vehicle surface where an array ofindividually configured split ring resonators are disposed, inaccordance with one embodiment. As an option, the section 2900 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the section 2900 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the section of a vehicle surface 2902 may be subjected tostresses and accompanying deformations during operation of the vehicle,and split ring resonators (split ring resonators) (shown in FIG. 29 asF₁₁, F₁₂, F₁₃, F₂₁, F₂₂, F₂₃, up and to F_(NN)) can be used to detectpossible changes within the material under such environmental stressesand deformations. The split ring resonators may be printed or appliedonto the spongy material of the vehicle (e.g. vinyl wrap of vehicle),and/or the combination of the resonators and spongy material may beplaced all over a vehicle or section of a vehicle surface of interest.

For example, the split ring resonators on the front bumper may undergoair pressure changes when the vehicle is in operation (such as, duringforward motion, thus creating a downward force on this section of thevehicle). Under the forces of the air pressure, the material thatcomposes the surface can deform slightly and, in accordance with thephenomenon described as pertains to FIG. 24B1 and FIG. 24B2, demonstratea change in resonant frequency of the material proportionate to thedegree of change or deformation of the material. While all the splitring resonators will be resonating simultaneously, a difference in oneof the split ring resonators or multiple of split ring resonators can bedetermined due to a change in the pitch that can be detected by astimulus/response comparator, such as may be implement in whole or inpart by a horn/receiver or similar device.

An array or matrix of split ring resonators over the vehicle surface2902 and the constituents are configured in such a way that thefrequency responses of any of the constituent members of the array donot collide with the neighboring split ring resonators. One suchconfiguration is shown and described as pertains to FIG. 30 .

FIG. 30 depicts a configuration 3000 of the split ring resonators in afrequency bin, in accordance with one embodiment. As an option, theconfiguration 3000 may be implemented in the context of any one or moreof the embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the configuration 3000may be implemented in the context of any desired environment. Further,the aforementioned definitions may equally apply to the descriptionbelow.

As shown, the split ring resonators (shown as F₁₁, F₂₁, up and toF_(NN)) may each reside in frequency bins. As the surface containing thesplit ring resonators undergoes deformation by deflection, the positivedeflection or negative deflection can change physical characteristics ofthe split ring resonator, thereby changing the inherent center frequencyof the member. The variation in the frequency response of a member isrepresented in FIG. 30 by the A symbols. This change in the resonantfrequency, even at its maximum, may not collide with the neighboringsplit ring resonators, as shown. Measuring the cyclic deflection overtime facilitates detection of cyclical stress (e.g. buffeting) as itoccurs on the vehicle surface. One such example for detecting time-baseddeflection variations is shown and described as pertains to FIG. 31 .

FIG. 31 shows a chart 3100 of detection of time-based variation ofdeflection, as indicated by time-based variation of the resonantfrequency, in accordance with one embodiment. As an option, the chart3100 may be implemented in the context of any one or more of theembodiments set forth in any previous and/or subsequent figure(s) and/ordescription thereof. Of course, however, the chart 3100 may beimplemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

As shown, the chart 3100 shows detection of time-based variations ofdeflection through ongoing measurement of cyclic deflection of the splitring resonators, which may allow for performing analysis of pressuresover a given control surface of the vehicle. For example, the foregoingtechniques of disposing an array of split ring resonators across acontrol surface vehicle, in combination with the technique of analyzingthe combined return from individual split ring resonators of thatcontrol surface, may allow identification of regions of the surface thatare experiencing cyclical stresses (e.g. buffeting). In some cases, thephysical property changes are indicative of relatively high frequency,dynamically changing property variations (e.g., vibration). Capturing aseries of a dynamically-taken series of responses/signatures, andcomparing such to a previously-taken series of calibrationresponses/signatures may facilitate dynamic non-destructive testing.Differences that are apparent between the two sets signatures may becorrelated to physical property changes, such as cyclical deformations(e.g. buffeting).

FIG. 32 depicts a signature classification system 3200 that processessignals received from sensors formed of carbon-containing tunedresonance materials, in accordance with one embodiment. As an option,the signature classification system 3200 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the signature classification system 3200 may be implemented inthe context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

In one embodiment, the signature classification system 3200 can beimplemented in any physical environment. More specifically, thesignature classification system 3200 depicts one example of how toclassify signals (such as, signatures). As shown, a ping signal of aselected ping frequency is transmitted at operation 3202. The pingsignal generation mechanism and the ping transmission mechanism can beperformed by any known techniques. For example, a transmitter module cangenerate a selected frequency of 3 GHz, and radiate that signal using ahorn or multiple horns and multiple receiving antennae. The designs andlocations of the tuned antennae can correspond to any tuned antennageometry, material and/or location such that the strength of the ping issufficient to induce (RF) resonance in proximate sensors. In someembodiments, several tuned antennae are disposed upon or withinstructural members that are in proximity to corresponding sensors (suchas mounted on and/or within any one or more of the wheel wells or avehicle). As such, when a proximal surface sensor is stimulated by aping, it may resonate back with a signature. At operation 3204, thatsignature can be received and stored in a dataset comprising receivedsignatures 3210. A sequence of transmission of a ping, followed byreception of a signature, can be repeated in a loop so as to capture aset of calibration signals, which in turn may be stored as calibrationpoints 3212.

The ping frequency can be changed (at operation 3208) in iterativepasses through decision 3206. Accordingly, as operation 3202 isperformed in the loop (via decision 3206), operation 3204 can receiveand then store the signatures 3210 (including a first signature 32101, asecond signature 3210 ₂, up to an N^(th) signature 3210 _(N)). Thenumber of iterations may be controlled by decision 3206. When the “No”branch of decision 3206 is taken (such as, when there are no furtheradditional pings to transmit in the iteration loop), then the receivedsignatures can be provided (operation 3214) to a digital signalprocessing module. The digital signal processing module classifies thesignatures (operation 3216) against a set of calibration points 3212.The calibrations points can be configured to correspond to particularping frequencies. For example, calibration points 3212 can include afirst calibration point 32121 that can correspond to a first ping andfirst returned signature near 3 GHz, a second calibration point 32122that can correspond to a second ping and second returned signature near2 GHz, and so on for any integer value “N” calibration points.

At operation 3220, classified signals are sent to a vehicle centralprocessing unit. The classified signals can be relayed by the vehiclecentral processing unit (such as vehicle central processing unit 116) toan upstream repository (such as upstream components 113) that hosts acomputerized database configured to host and/or run machine learningalgorithms. Accordingly, a vast amount of stimulus related to signals,classified signals, and signal responses can be captured for subsequentdata aggregation and processing. A database of the machine learningsubsystem (e.g., a training model) can be formed or “trained” byproviding a set of sensed measurements which in turn are correlated toconditions related to vehicular performance. Once the database has beencomputationally prepared, or “trained”, then during the operation of thevehicle, the measured deflection (such as, air pressure) of a particularportion of an airfoil component can be compared to the calibrationpoints, and the comparison yields a delta in frequency that correspondsto a variation in deflection which in turn corresponds to a particularair pressure. Other potential conditions or diagnoses can be determinedby the machine learning system. The conditions and/or diagnoses and/orsupporting data can be made available to instrumentation in the vehicleto complete a feedback loop. In some cases, instrumentation in thevehicle provides visualizations that can be acted upon (such as, by adriver or by an engineer).

FIG. 33 shows a depiction 3300 of split ring resonators disposed inand/or on a drone, and/or a drone platform, in accordance with oneembodiment. As an option, the depiction 3300 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the depiction 3300 may be implemented in the context of anydesired environment. Further, the aforementioned definitions may equallyapply to the description below.

As shown, a drone 3302 may include one or more split ring resonators3304. In one embodiment, the drone 3302 may be used to transport apackage 3306. Of course, it is to be appreciated that the drone 3302 maybe configured for transport of other items (such as a camera, weathersensing instruments, animals, medical supplies, food, goods, cargo,payloads, etc.). Additionally, in other embodiments, the drone 3302 maybe configured for military or tactical purposes (including configured asan unmanned combat aerial vehicle). Further, as described hereinbelow,the drone 3302 may be configured as a passenger drone, an unmannedaerial vehicle (UAV), and/or an autonomous aerial vehicle (AAV). In oneembodiment, the drone 3302 may be capable of vertical take-off andlanding (VTOL) and/or electric vertical take-off and landing (eVTOL).

Additionally, a drone landing pad 3308 is provided, which may includeone or more split ring resonators 3312. A target location 3310 to alignthe drone 3302 and the drone landing pad 3308 is also provided.

In various embodiments, the one or more split ring resonators 3304 maybe used to facilitate real-time sensing of a physical state of the drone3302 and/or environmental conditions external to the drone 3302. Suchreal-time sensing may occur millisecond-by-millisecond, and may be usedto detect structural changes within the drone 3302 before it becomes aproblem, and/or to alter a course of the drone 3302 to reach an intendeddestination (such as the target location 3310). For example, in oneembodiment, should a propeller on the drone 3304 suffer material fatigue(and be prone to break), a split ring resonator located on the propellermay determine a structural change (in terms of a change of frequency).Additionally, any element of the drone 3302 may be monitored such thatany structural change can be detected before the negative effects of thechange are observed.

In another embodiment, the drone 3302 may initiate a takeoff or landingon the drone landing pad 3308. Real-time sensing of the state of thedrone 3302 (by the one or more split ring resonators 3304) may protectboth the drone 3302 and/or the drone landing pad 3308. In this manner,the one or more split ring resonators 3304 may detect changes beforeand/or after takeoff. It is to be noted that the one or more split ringresonators 3312 on the drone landing pad 3308 may additionally be usedto sense both a state of the landing pad 3308 and/or a position of thedrone 3302 (regardless of whether the drone 3302 has the one or moresplit ring resonators 3304). Further, when landing, the one or moresplit ring resonators 3304 on the drone 3302 or the one or more splitring resonators 3312 on the drone landing pad 3308 may be used todetermine, in real-time, a pinpoint location of the drone 3302 as itapproaches the drone landing pad 3308. In this manner, the one or moresplit ring resonators 3304 and/or 3312 may be used for precision landingcapabilities.

The one or more split resonators 3312 of the drone landing pad 3308 mayadditionally be used to determine a state of the drone landing pad 3308such that material fatigue and/or component failure can be detectedbefore visually manifested.

In another scenario, after landing, a state of the drone 3302 may beassess by receiving health related data from the one or more split ringresonators 3304. For example, the drone 3302 may pass through a dronehealth system which may broadcast a wireless signal. Each of the one ormore split ring resonators 3304 may provide a frequency response thatmay correspond with structure health (in terms of material fatigue andcomponent failure) of the drone 3302. In this manner, the split ringresonators 3304 may be used to detect a state of health of the drone3302 before, during, and after takeoff and/or landing. The state of thehealth may be used to alert and/or be communicated to a human/userand/or an autonomous system.

In this manner, an autonomous system of heath checking for a fleet ofdrone may be achieved. When a drone arrives at a landing location, itmay be inspected and assessed. If a split ring resonator indicates astructural issue with the drone, it may be further inspected (e.g.manual inspection, etc.) and/or repaired. If no issues are found withthe drone, it may receive a “good health” designation and be ready to besent out again. In this manner, continual management of the drones maybe achieved with respect to health integrity of the fleet, which inturn, may satisfy legal and social constraints on use of drones(particularly within consumer air space).

FIG. 34 shows a depiction 3400 of split ring resonators disposed inand/or on an aerial vehicle, in accordance with one embodiment. As anoption, the depiction 3400 may be implemented in the context of any oneor more of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the depiction3400 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, an unmanned aerial vehicle (UAV) 3402 may include split ringresonators located on the aerial vehicle body 3404, structuralcomponents 3406, and/or propeller components 3408. Of course, it is tobe appreciated that split ring resonators may be located in and/or onany and/or all components of the drone 3404.

In various embodiments, the split ring resonators (such as those locatedon the aerial vehicle body 3404, structural components 3406, and/orpropeller components 3408) may be used to obtain real-time (withmillisecond time granularity) measurements associated with the unmannedaerial vehicle 3402, including but not be limited to vibration, strain,dimensional and/or material property changes, pressure, and temperature.

For example, with respect to vibration, the split ring resonators mayread vibrational frequency (from Hz level to 100s of KHz level).Additionally, in one embodiment, accelerometers and other noncontactdisplacement sensors may be used to measure low through high frequencyvibration (e.g., from very low frequencies in the low hertz range suchas in large bridge-like structures to higher vibrations such as arefound in supersonic applications—up to 100s of kilohertz). With respectto strain, the split ring resonators may detect componentflexion/torsion, as well as structural fatigue/failure. With respect todimensional and/or material property changes, the split ring resonatorsmay determine whether elastomer components (such as those found, forexample, in tires, belts, hoses, etc.) need to be replaced (due to wearand aging). Further, dimensional and/or material property changes may beused to determine a distance to ground for landing (as describedhereinabove FIG. 33 ). With respect to pressure, the split ringresonators may be used to detect air pressure, differential airpressure, and/or cyclical changes in air pressure. Additionally, withrespect to temperature, the split ring resonators may detect surface andcomponent internal temperatures.

As such, split ring resonators found in or on components through theunmanned aerial vehicle 3402 may be used to detect parametricmeasurements associated with a state of health of the unmanned aerialvehicle 3402. Further, more than one measurement may be simultaneouslyreceived. For example, in response to a wireless ping, each of the splitring resonators may provide a frequency response. Such frequencyresponse may be calibrated, in one instance, to a measurement ofpressure, whereas another frequency response may be calibrated, inanother instance, to material property changes. As such, responses fromall of the split ring resonators may be received, which in turn, mayprovide a simultaneous result of all sensor parameters associated withthe unmanned aerial vehicle 3402.

FIG. 35 shows a depiction 3500 of split ring resonators disposed inand/or on an aerial vehicle, as well as landing location sensors, inaccordance with one embodiment. As an option, the depiction 3500 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the depiction 3500 may be implemented inthe context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, an unmanned aerial vehicle 3502 may be capable of verticaltake-off and/or landing (VTOL and/or eVTOL). It is to be appreciatedthat, in other embodiments, the unmanned aerial vehicle 3502 may beconfigured for other takeoff capabilities (e.g. conventional takeoff andlanding, short takeoff and landing, etc.).

One or more split resonators may be found on the unmanned aerial vehicle3502 including being located on the aerial vehicle body 3504, structuralcomponents 3506, and/or landing gear 3508. Of course, consistent withFIG. 34 , the one or more split resonators may be located anywhere (andin any degree of quantity) on the unmanned aerial vehicle 3502, and maybe used to provide sensor related information.

As an example, the split ring resonators located on the unmanned aerialvehicle 3502 may be distributed throughout the surface. Additionally,lightweight antennas may additionally be distributed throughout theunmanned aerial vehicle 3502. In one embodiment, the split ringresonators and antennas may be redundant (especially formission-critical components, for safety constraints, etc.). Such splitring resonators may provide real-time simultaneous sensing (inmilliseconds). Further, condition signatures may be associated withsimultaneous feedback responses from the split ring resonators. Forexample, a condition signature may be associated with a componentfailure, an external condition (weather, flying pattern, etc.), etc.Further, the split ring resonators may be arranged to allow fortriangulation positioning to assist with pinpoint landings (consistentwith as described herein with respect to FIG. 33 ).

To that end, the split ring resonators may include location sensors3512, may be used to calculate landing gear flexion 3510, surfaceflexion 3518, propeller flexion 3514, and/or air pressure 3516. Asemphasized elsewhere, the split ring resonators may be used in anycapacity in relation to takeoff, flight, landing, management, etc. ofthe unmanned aerial vehicle 3502, including but not limited to torsion,tire wear, air speed, air pressure, flexion of vehicle component, etc.

In one embodiment, the location sensors 3512 may operate to pinpoint alocation for precise landing. Further, split ring resonators 3522located in and/or on the surface of the ground 3520 may additionally beused to assist with achieving a precise landing.

FIGS. 36A and 36B show two depictions 3600 of split ring resonatorsdisposed in and/or on aircraft, in accordance with one embodiment. As anoption, the two depictions 3600 may be implemented in the context of anyone or more of the embodiments set forth in any previous and/orsubsequent figure(s) and/or description thereof. Of course, however, thetwo depictions 3600 may be implemented in the context of any desiredenvironment. Further, the aforementioned definitions may equally applyto the description below.

As shown, an aircraft 3602 includes one or more split ring resonatorsthat are located in and/or on various locations of the aircraft 3602,including, but not limited to an engine 3604 (jet, propeller, etc.), awing 3606, a horizontal stabilizer 3608, a fuselage 3610, and/or tires3612. It is to be appreciated that any number of split ring resonatorsmay be found on the aircraft 3602, and a purpose of the split ringresonator may differ. For example, split ring resonators located at thefront of the aircraft 3602 may be used to gather external weatherconditions (air pressure, temperature, wind speed, etc.), split ringresonators located on tires may be used to determine tread life andstate, and/or split ring resonators located in the engine may be used toensure safety and lack of material fatigue. In some embodiments, acondition signature may be created and correlated with known conditions(weather patterns, signs of material fatigue, etc.). Additionally, afrequency from a split ring resonator may be used for more than onecondition signature simultaneously. For example, a split-ring resonatormay be used for determining tread thickness, and may also be used forstiction measurements, hydroplaning detection, etc.

It is to be appreciated that although a commercial aircraft is shown inthe two depictions 3600, any aircraft (commercial, military, personal,etc.) may be applicable. Additionally, use of split ring resonators inaircraft may provide continuous millisecond-by-millisecond changesbefore takeoff, continuously during flight, and during landing. Suchchanges may include structural parameter changes (e.g. fatiguethresholds, impending component failure, etc.), which in turn, may causealerts to systems and personnel. For example, triggering an alert maycause an aircraft to avoid aircraft, or to land safely before animpending failure event occurs.

FIG. 37A shows a depiction 3700 of split ring resonators disposed inand/or on a rocket, in accordance with one embodiment. As an option, thedepiction 3700 may be implemented in the context of any one or more ofthe embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the depiction 3700 maybe implemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

As shown, a spaceship 3702 may include one or more split ring resonatorslocated through the spaceship 3702, including, but not limited to, thewing 3704, the elevon 3714, the engine 3708, the flight deck 3710,and/or the cargo bay 3708. It is to be appreciated that any number ofsplit ring resonators may be found on the spaceship 3702.

Use of split ring resonators in spaceships may provide continuousmillisecond-by-millisecond changes before takeoff, continuously duringflight, and during reentry. Such changes may include structuralparameter changes (e.g. fatigue thresholds, impending component failure,etc.), which in turn, may cause alerts to systems and personnel.Further, spaceships (often termed orbiters) are often attached to arocket booster. Generally, a structural failure to any component oneither of the spaceship or the rocket booster would often result incomplete failure for both the spaceship and the rocket booster. Use ofsplit ring resonators, however, would ensure that any structuralparameter change (to either the spaceship or the rocket booster) couldbe detected before impacting either the spaceship or the rocket booster.In some embodiments, a structural parameter change may cause thespaceship and the rocket booster to disengage to preserve the one or theother (based on the structural parameter change identified).

FIG. 37B shows a depiction 3701 of split ring resonators disposed inand/or on a rocket, and/or a landing platform, in accordance with oneembodiment. As an option, the depiction 3701 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the depiction 3701 may be implemented in the context of anydesired environment. Further, the aforementioned definitions may equallyapply to the description below.

As shown, a spaceship 3709 may be attached to a rocket booster 3707.Split ring resonators may be located and found on each of the spaceship3709 and the rocket booster 3707. Further a launch pad for the spaceship3709 and the rocket booster 3707 is shown, including a launcher platform3703, a flame pit 3711, platform trusses 3713, and/or a launcher servicestructure 3705. Split ring resonators may be located and foundthroughout each component of the launch pad of the depiction 3701. Inthis manner, split ring resonators located in and/or on parts of thelaunch pad may be used to detect structural parameter changes (e.g.fatigue thresholds, impending component failure, etc.), which in turn,may cause alerts to systems and personnel. For example, a structuralfail (in any of the components) may cause a launch to be aborted.Additionally, after the launch has commenced (but before liftoff), astructural fail may additional cause a launch to be aborted. Thus, anystructural fail (at any point) may be the basis for a launch to beaborted, and/or for corrective action to be implemented.

In this manner, early warning systems may be based on split ringresonators found through the launch pad, the spaceship, and/or therocket booster, and/or any component related thereto, and real-time datamay be obtained to ensure safe remediation of any detected change.

Further, for any type of airborne vehicle, split ring resonators may beused as low-cost resonant sensors for safety. For example, split ringresonators may be used to detect excess vibration on components, detectand monitor microcracks in materials, monitor local temperatures ofnonmetallic component surfaces (in providing instantaneous values aswell as historical/cyclical changes), monitor local temperatures withinnonmetallic components (in providing instantaneous values as well ashistorical/cyclical changes), provide pinpoint position accuracy (forprecise landings, as an example), and/or may be installed intomaterials, onto surfaces and/or below surfaces (such as paintedsurfaces).

FIG. 38A is a flow chart 3800 relating to reporting feedback from splitring resonators, in accordance with one embodiment. As an option, theflow chart 3800 may be implemented in the context of any one or more ofthe embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the flow chart 3800 maybe implemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

The flow chart 3800 relates to one embodiment where sensor data isreceived from one or more split ring resonators, and one or more actionsare taken in response.

As shown, the flow chart 3800 begins with receiving sensor data from acalibrated sensor (step 3802). The calibrated sensor may include one ormore split ring resonators, calibrated based on a natural resonance. Itis determined (decision 3804) whether the sensor data is within apredetermined range. For example, the sensor data may be correlated witha condition signature (where known deviations are correlated with knownfailures and/or conditions). If the sensor data is within range (orwithin an allowed condition signature), the method returns tocontinuously receiving sensor data (per step 3802). Of course, theinterval for receiving sensor data may be predetermined and/or adjustedas needed.

If the sensor data is not within range, then the flow chart 3800advances to decreasing testing interval period (step 3806). In oneembodiment, step 3806 may be optional. For example, the testing intervalperiod may already be near continuous (per step 3802), in which casethere may not be a need to decrease the testing interval period. Inresponse (or simultaneous with) to step 3806, an alert may be triggered(step 3808), and a report may be generated (step 3810).

In some embodiments, an alert and/or a report in relation to thenot-in-range sensor data may be used to inform and/or alert a human(e.g. operator, supervisor, etc.), saved to a repository (e.g. storage,etc.), inform and/or alert an organization (e.g. EnvironmentalProtection Agency, Department of Motor Vehicles, etc.), etc. It isenvisioned that such not-in-range sensor data may also be used totrigger automated actions (e.g. AI integrated systems, etc.), causeautomated setting alteration(s) on the vehicle (or an apparatus in whichthe split ring resonators are located), and/or take any other automatedaction (without intervention of a human).

FIG. 38B is a flow chart 3812 relating to landing an aerial vehicleand/or drone using split ring resonators, in accordance with oneembodiment. As an option, the flow chart 3812 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the flow chart 3812 may be implemented in the context of anydesired environment. Further, the aforementioned definitions may equallyapply to the description below.

The flow chart 3812 relates to one embodiment where sensor data isreceived from one or more split ring resonators (located on site) toassist with pinpoint landing capabilities. It is to be appreciated thatas similar flow could be created for use of split ring resonatorslocated on an aerial vehicle (rather than relying on site-basedsensors).

As shown, the flow chart 3812 starts with an aerial vehicle approachinga landing site (step 3814). It is determined whether the aerial vehicleis within a set range (such as a predetermined distance from the landingpad) (decision 3816). In one embodiment, determining whether an aerialvehicle is within a set range (per decision 3816) may rely, at least inpart, on split ring resonators located on the aerial vehicle.

Once the aerial vehicle is within a set range, data may be received fromsite sensors (step 3818). Data from such site sensors may be sent to theaerial vehicle such that position adjustments may be affected (decision3820). When the position does not need further alteration, the aerialvehicle may be landed (step 3822). Of course, it is to be appreciatedthat decision 3820 may occur continuously as the aerial vehicleapproaches the landing pad, such that real-time adjustments to theposition of the aerial vehicle may be made.

In one embodiment, the site sensors (per step 3818) may be used totriangulate the exact position of the aerial vehicle. As can beappreciated, the flow chart 3812 provides just one example of how splitring resonators may be used and assist in landing an aerial vehicle.

FIG. 39 shows a depiction 3900 of meta-materials in a dielectric matrix,and circuitry relating thereto, in accordance with one embodiment. As anoption, the depiction 3900 may be implemented in the context of any oneor more of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the depiction3900 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

Within the context of the present description, meta-materials mayinclude any material engineered to have a physical property that is notfound in naturally occurring materials.

As shown, in SEM image 3902, meta-materials may be tuned in a dielectricmatrix. For example, meta-materials may be selected for frequencyselective properties, including where the meta-materials are innatelytuned and constructed in application. Additionally, the meta-materialsmay provide frequency selective conductivity without being directcurrent conductive. Further, such meta-materials may conduct andmaintain a connection without touching (unlike standard conductiveink/flakes/coating which must touch in order conduct and maintain aconnection).

The arrangement of meta-materials tuned in a dielectric matrix (per SEMimage 3902) may be shown via lumped circuits 3904, where a seriesresistance with minimum impedance at resonant frequency, or a parallelresistance with maximum impedance at resonant frequency may be achieved.It is to be appreciated that the arrangement of meta-materials may bearranged in either a series resistance and/or a parallel resistance.

In various embodiments, the meta-materials in a dielectric matrix may bearranged in a split ring resonator 3906 which may be represented in acircuitry type configuration 3908. Such configuration 3908 may includean inductor associated with the ring, and a capacitor associated withthe gap of the split ring resonator. Such configuration should beconstrued in a manner consistent with FIGS. 24B1 and 24B2 discussedhereinabove.

Use of meta-materials as frequency selective materials may allow forcontinued flexing (of the material) without degradation in conductance.Additionally, frequency tuning may allow for increased signal to noiseratio for better detection and resolution. Further, other parameters(temperature, stress strain, etc.) may be directly measured through thestretching, deforming, and/or temperature readings of the dielectricmatrix.

In this manner, meta-materials may be used in and/or on a split ringresonator, which in turn, may provide frequency selective conductivitywithout being DC conductive. Further, high frequency conductivity ofmeta-materials may allow for use in split ring resonators.

FIG. 40 shows a depiction 4000 of a split ring resonator embedded withinan open or closed cell material, in accordance with one embodiment. Asan option, the depiction 4000 may be implemented in the context of anyone or more of the embodiments set forth in any previous and/orsubsequent figure(s) and/or description thereof. Of course, however, thedepiction 4000 may be implemented in the context of any desiredenvironment. Further, the aforementioned definitions may equally applyto the description below.

As shown, a split ring resonator 4006 may be embedded between a firstlayer 4002 and a second layer 4004. In various embodiments, the materialof the first layer and/or the second layer may include open or closedcell (selected or coated) material. Such material may have a specificpermittivity that is a mix of the material and of air in the poreswithin the material itself, such that when the air flow compresses thefoam drives out the air and the aggregate permittivity becomes that ofthe material (the open or closed cell foam). As a result of the factthat the material's permittivity is much higher than the air, thecompression of the material would result in a downshift of frequency.

To describe it from an alternative perspective, embedding the split ringresonator 4006 in a foam-based material allows for a greater resonancefrequency (compared to if the split ring resonator responded by itself).This greater resonance frequency is due, at least in part, to thefoam-based material deforming, and when the deformation occurs, there isa direct and great correlation with a change of permittivity of thefoam-based material.

Additionally, in another embodiment, a split ring resonator may beprinted onto the top of the open or closed cell material foam, with aground plane on the back with foam material in-between the top andground plane levels. The distance between the front sensor to the groundplane (with the foam in-between) may cause a frequency shift (like acapacitor). In this manner, the foam material may function as a pressuresensor and the presence of the foam may serve to shift the resonantfrequency up or down. For example, if the foam element(s) is deformed ordeflected (push in or pulled out), the foam elements can be measured asa change of the split ring resonators.

As such, as detailed herein, a split ring resonator may provide aresponse to a wireless ping/chirp/query. Additionally, using afoam-based material to encase the split ring resonator may amplify thesplit ring resonator's response. Again, the deformation of thefoam-based material is greater than, for example, a semi-rigid material,which in turn, translates to a greater permittivity difference(comparing again a foam-based material to a semi-rigid material). Withinthe context of FIG. 24B4, a foam-based material may have a similar typeresponse (with the y-axis coordinate measuring permittivity rather thanfrequency). Additionally, in one embodiment, such permittivity may beunipolar or bi-polar. For example, in some cases (e.g., in turbulentsituations), a positive pressure as well as negative pressure may existon the surface. Within the context of the present description, asemi-rigid material refers to a stiff material that is capable offlexing. A foam-based material refers to a cellular spongy material.Comparing a semi-rigid material to a foam-based material, the foam-basedmaterial is capable of greater compression and deformation (given itsspongy form). As such, using foam-based material in combination withsplit ring resonators (as detailed herein) may allow for greateramplification of the response (which in turn may correlate withinstrumentation that can operate at lower frequency and power levels).

The combination, therefore, of a split ring resonator with anaccompanying material and/or substrate (e.g. semi-rigid material,foam-based material, concrete, rubber, polymers, etc.) may have anensemble effect. Within the context of the present description, anensemble effect refers to the frequency response of a split ringresonator in combination with an accompanying material and/or substrate.

FIG. 41 shows a depiction 4100 of pressure sensors using open or closedcell material, in accordance with one embodiment. As an option, thedepiction 4100 may be implemented in the context of any one or more ofthe embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the depiction 4100 maybe implemented in the context of any desired environment. Further, theaforementioned definitions may equally apply to the description below.

In function, a wave pulse may propagate from an antenna (located on thevehicle 4104 and/or a surrounding object/location), which in turn mayimpinge on an object (such as the unoptimized sensors 4104) that hasreal and imaginary physical materials components that either reflect orabsorb the energy. This, in turn, may produce a form of analog telemetryvia wireless communication (where transmission of temperature, pressure,and/or other measurements may occur by reflection or absorption of thewave pulse), which in turn, may provide a remote low-cost parametersensing of the physical world.

Real-world testing of the vehicle 4102 with sensing data is shown inFIG. 42 .

FIG. 42 shows a depiction 4200 of wind pressure sensing data using openor closed cell material, in accordance with one embodiment. As anoption, the depiction 4200 may be implemented in the context of any oneor more of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the depiction4200 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, the depiction 4200 is of wind pressure sensing data based on avehicle (such as the vehicle 4102). The wind pressure sensor may beconstructed in a manner consistent with FIG. 40 . Additionally, it is tobe appreciate that FIG. 42 displays a single use case scenario (for windpressure). Similar sensing data may be obtained for other metrics(temperature, pressure, speed, etc.).

The depiction 4200 shows three case scenarios: (1) frequency based on nomovement of the vehicle; (2) frequency based on straight trackacceleration of the vehicle; and (3) frequency based on the vehicleslowing down on a turn. As can be observed, each of the case scenariosproduces a separate and distinct frequency measurement. Such frequencymeasurement may be correlated with a condition signature, as describedhereinabove. Additionally, the stars found on each of the lines areindicative of maxima/minima data points.

FIG. 43 shows a depiction 4300 of a path and circuitry relating tofrequency selective conductivity, in accordance with one embodiment. Asan option, the depiction 4300 may be implemented in the context of anyone or more of the embodiments set forth in any previous and/orsubsequent figure(s) and/or description thereof. Of course, however, thedepiction 4300 may be implemented in the context of any desiredenvironment. Further, the aforementioned definitions may equally applyto the description below.

As shown, the depiction 4300 includes an image 4301 of current materials4302 and meta-materials 4304. As can be observed, current materialsrequire a DC current based on a direct connection which allows currentto flow. Such current materials may be represented by circuit 4306. Incontrast to such conventional systems, use of meta-materials 4304 mayallow conductivity to be achieved through resistive and reactivepathways. Such pathways may be based on a non-direct connection (whereeach pathway and/or node does not need to be touching) in order to beconductive. Circuit 4308 represents use of the meta-materials toestablish conductivity.

FIG. 44 shows a depiction 4400 of many industries in which the use ofsplit ring resonators may be applicable, in accordance with oneembodiment. As an option, the depiction 4400 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the depiction 4400 may be implemented in the context of anydesired environment. Further, the aforementioned definitions may equallyapply to the description below.

As shown, the depiction 4400 includes a variety of exemplary world-wideindustry applications where resonance frequency shifts associated withsplit ring resonator(s) may offer early detection capabilities withregard to literally hundreds of potential scenarios, thus providing theability to remediate and adjust where potential issues may bediscovered. Data associated with resonance frequency shifts of splitring resonator(s) may apply to nearly every industry and market,including but not limited to: utilities, space travel and exploration,agriculture, power production, manufacturing, vehicular safety,commercial tire dynamics, professional sports, forging, construction,molecular analysis and degradation, biomedical, battery composition,aviation and/or aeronautics, nautical, consumer packaged goods, bridgesand roadways, etc. Some of such industries (and applicability of splitring resonators) have been detailed herein.

For purposes of being as precise as possible, as well as showingpotential applicability of use of split ring resonators (and resonancefrequency shifts relating thereto) to many other industries, additionalmaterial is provided hereinbelow.

FIG. 45 shows a water droplet sensing vehicle application 4500, inaccordance with one embodiment. As an option, the water droplet sensingvehicle application 4500 may be implemented in the context of any one ormore of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the waterdroplet sensing vehicle application 4500 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the water droplet sensing vehicle application 4500 is shownwithin the context of a vehicle, with split ring resonators (SRRs) 4502shown around the periphery of the windshield, and an interrogationsignal 4504 on a SRR. It is to be appreciated that the SRRs 4502 may belocated anywhere around the windshield of the vehicle, although as shownfor exemplary purposes, they may be located along the edge of thewindshield (so as not to disturb the optics of the glass). Theinterrogation signal 4504 may be sent from any location within thevehicle (e.g. along the dashboard, within the structure of the vehicle,etc.).

Further, the SRRs 4502 may be further positioned on a housing foroptical instruments (e.g. camera, LiDAR, nonlinear photodiode, etc.)and/or other sensing instruments (e.g. radar, ultrasonic sensors, etc.)of a vehicle. In one embodiment, the vehicle may include an autonomousvehicle.

It is to also be appreciated that the SRRs 4502 may be located at anylocation where sensing water may be needed. For example, SRRs 4502 maybe located on or near light sources, a window, a screen, etc. Further,the SRRs 4502 may be located at any location where sensing a fluid maybe needed. For example, SRRs 4502 may be located within a gascanister/tank, hydraulic fluid reservoir, transmission fluid reservoir,engine oil reservoir, engine coolant reservoir, brake fluid reservoir,differential fluid reservoir, steering fluid reservoir, hydraulic clutchfluid, window washing fluid reservoir, and/or any other fluid source.The SRRs 4502, in one embodiment, may be configured for the fluid to besensed.

In various embodiments, the interrogation signal 4504 may be used todetermine a concentration of water at each of the SRRs 4502. Forexample, a concentration of water may be correlated with a permittivity(or dielectric constant) such that a higher concentration of waterresults in a first permittivity and a lower concentration of waterresults in a second permittivity. Thus, the SRRs 4502 can beinterrogated via the interrogation signal 4504 to determine a waterconcentration. In like manner, the SRRs 4502 may be tuned to otherfluids such that a change of permittivity may be measured (andcorrelated with a concentration of the fluid).

As such, in various embodiments, the SRRs 4502 may determine thepresence of water droplets based on the state, or change of, dielectricconstant and/or permittivity of the material to which the SRRs areaffixed.

In one embodiment, the interrogation signal 4504 may be associated withor connected to the vehicle's electronics (e.g. ECU, etc.). For example,the interrogation signal 4504 may be associated and/or compliant withauto electronics protocols (e.g. Autosar, etc.).

In any manner, the SRRs 4502 may be used to detect water droplets, suchas water concentration, on a surface (such as a windshield). Theinterrogation signal 4504 may be used to interrogate the SRRs 4502 todetermine whether water droplets have accumulated or formed on thesurface.

In one embodiment, in response to detecting water droplets, the vehiclemay take an action to remedy the situation, such as activating adefrosting function to reduce the amount of water droplets on thesurface. In another embodiment, an array of SRRs may be used to generatea collective interrogation response, such that multiple signals from thearray of SRRs may provide a water droplet mapping (of water dropletconcentrations) across the entire (or a substantial portion of the)surface. In this manner, the array of SRRs may be used to create amapping of water droplet concentration. In one embodiment, selectiveremedial action, such as applying a defrosting function to only aportion of the windshield, may be based on such mapping.

FIG. 46 shows a method 4600 for remedying sensed water droplets, inaccordance with one embodiment. As an option, the method 4600 may beimplemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the method 4600 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the method 4600 begins with determining concentration of waterparticle condensate. See step 4602. In one embodiment, the determinationof step 4602 may include a determination whether the concentrationexceeds a maximum preconfigured threshold. Additionally, such maximumpreconfigured threshold may take into consideration one or more sensorreadings, such as readings from multiple SRRs, a barometer sensor, alocation sensor (e.g. for determining whether the vehicle is near water,etc.), etc. Input from these sensors may be used for prescribing arecommended course of action to remedy the detected water particlecondensate.

Additionally, per step 4604, one or more remedial measures may beapplied to reduce the concentration of the water particle condensate.For example, a defrosting action, an electric heat plate (embeddedwithin or near the windshield), etc. may be activated to reduce theconcentration of the water particle condensate. In various embodiments,one or more remedial modules may receive the input from the sensors,determine appropriate remedial action, implement such remedial action,and determine when to stop the remedial measure(s).

Further, per step 4606, the remedial measures may be stopped once theconcentration of the water particle condensates reaches a predeterminedthreshold. For example, in response to activating a defrosting action,the circulating air may reduce the water particle condensate on thesurface of the windshield. In one embodiment, the defrosting action maybe stopped once the concentration falls below a predetermined threshold.In another embodiment, the remedial action may be deactivated after aset time period expires from reaching the predetermined threshold. Forexample, the SRRs being interrogated may indicate that the waterparticle condensate may be below the preconfigured threshold. However,the SRRs being interrogated may be located only along the periphery ofthe surface (thereby leaving the middle of the windshield still foggedup). Thus, the remedial action may continue on for a predeterminedamount of time until it is expected that the water particle condensatehas been removed from a location other than where the SRRs are located.

In another embodiment, the SRRs may be configured such that they do notdistort the optics of the windshield (e.g. using nanoparticle sensors,using fiber optics configuration, etc.), such that the SRRs may beintegrated throughout the entire surface for more accurate interrogationand feedback.

In this manner, the surface may sense when water droplets accumulate,and remedial actions may be applied to offset the water droplets.

FIG. 47 shows a water droplet sensing aircraft application 4700, inaccordance with one embodiment. As an option, the water droplet sensingaircraft application 4700 may be implemented in the context of any oneor more of the embodiments set forth in any previous and/or subsequentfigure(s) and/or description thereof. Of course, however, the waterdroplet sensing aircraft application 4700 may be implemented in thecontext of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, water droplet sensing aircraft application 4700 includes awing 4702 which may be of an aircraft, a drone, a rocket, an aerialvehicle, etc. The wing 4702 may include a surface 4704 on which iceparticles 4706 may accumulate. Additionally, the surface 4704 mayinclude split ring resonators (SRRs) 4708 (such as on the surface orbelow the surface). The SRRs 408 may be used determine the presence ofthe water droplets. As described hereinabove, the SRRs 4708 may beembedded within the material used for the wing 4702.

In the event that the ice particles 4706 are sensed on the surface 4704by the SRRs 4708, the aircraft may take remedial measures to removeand/or decrease the ice particles 4706 that have accumulated. Forexample, the remedial measures may include physically moving wings flapson the aircraft, activating heaters, activating de-icing agent, etc.

FIG. 48 shows a leaky antenna interrogation system 4800 for waterdroplet sensing, in accordance with one embodiment. As an option, theleaky antenna interrogation system 4800 may be implemented in thecontext of any one or more of the embodiments set forth in any previousand/or subsequent figure(s) and/or description thereof. Of course,however, the leaky antenna interrogation system 4800 may be implementedin the context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the aircraft 4802 may include a leaky antenna 4804 integratedwithin the structure of the aircraft 4802 itself. The leaky antenna 4804may be used in a variety of communication systems (particularly inunderground or confined environments). As such, although the leakyantenna 4804 is shown specifically within the context of the aircraft4802, it is to be appreciated that it may be used in a variety ofcontexts (e.g. within buildings, tunnels, homes, tractor trailers,trains, mines, subways, underground, bridges, long corridors,warehouses, etc.). In one embodiment, the leaky antenna 4804 may beconfigured to provide radio frequency (RF) signal coverage in areaswhere traditional antennas may not be effective due to physicalobstructions, such as walls or tunnels.

Additionally, in one embodiment, the leaky antenna 4804 may beconfigured to allow a radio frequency (RF) signal to “leak” out of thecable, which in turn, may provide coverage along the entire length ofthe cable. As such, signal propagation may be increased along a surface(or within a confined space) by using the leaky antenna 4804.

Further, the leaky antenna 4804 may operate in the context of, forexample, FIGS. 45 and/or 46 (among others). For example, the leakyantenna 4804 may be used to interrogate split ring resonators (SRRs).Further, the interrogation may include determining the presence of waterdroplet formation.

In one particular example, a surface of the aircraft 4802 may begin toaccumulate ice particles. SRRs embedded throughout the surface (or nearthe surface) of the aircraft may detect the presence of water droplets.An interrogation signal sent via the leaky antenna 4804 may allow forinterrogation of all SRRs within the aircraft 4802. In this manner, theSRRs may allow for a sensed real-time, real-state mapping of waterdroplets across the entire aircraft 4802.

It is to be appreciated that the application to water droplets is butone example. In a similar manner, the SRRs may be configured in avariety of other settings with similar detection resulting. For example,SRRs may be embedded within brake pads such that when brake pads areworn down, the dielectric constant (and/or permittivity) may alter,which in turn, may be communicated via an interrogation system. As such,the SRRs may be configured for a variety of applications based on thedesired aspect that is to be sensed and/or monitored.

FIG. 49 shows an architecture 4900 for leaky feeder antenna, inaccordance with one embodiment. As an option, the architecture 4900 maybe implemented in the context of any one or more of the embodiments setforth in any previous and/or subsequent figure(s) and/or descriptionthereof. Of course, however, the architecture 4900 may be implemented inthe context of any desired environment. Further, the aforementioneddefinitions may equally apply to the description below.

As shown, the architecture 4900 shows one possible arrangement withinthe context of an aircraft communication's system. Such a system mayinclude radios 4902 (such a satellite and/or ground systems, etc.) whichmay be in communication with an onboard processing and server 4904. Theonboard processing and server may be in communication with a Wi-Fiaccess point 4906 and/or a cellular picocell 4908, each of which, inturn, may be in communication with a diplexer 4910. The diplexer 4910may be in communication with the leaky feeder antenna 4912. Thus, theleaky feeder antenna 4912 may be integrated into the communicationssystem of an aircraft. Additionally, the leaky feeder antenna 4912 mayinclude a system and/or assembly associated with the leaky feederantenna 4912.

Additionally, as discussed herein, the architecture 4900 may be used incombination with SRRs to detect water droplet accumulation. For example,the leaky feeder antenna 4912 may be used to interrogate the SRRs todetermine a state of water droplet accumulation on a wing of anaircraft. In response to the detection, the leaky feeder antenna 4912may communicate such information directly to a control module of theaircraft for appropriate remedial action.

As discussed earlier, split ring resonators may be embedded in orprinted on other materials (other than concrete barriers of FIG. 22A2and/or metal barriers of FIG. 22A3) encompassing a wide range ofapplications within equally wide range of global industries. In thismanner, measuring resonance frequency shifts may occur in nearly anyapplication where split ring resonators can be embedded or printed (on asurface, within a material, etc.). Further, split ring resonators may beused not only to determine a shift in resonance frequency (which may beassociated with a signature indicative of a physical condition), but mayalso be used to control an aspect in response to receipt of such input.For example, a temperature sensor may have split ring resonatorsembedded therein such that when a predetermined temperature is reached,an external unit (air conditioner, heater, air vent, etc.) may beactivated until the ambient temperature reaches the predeterminedtemperature. In some instances, taking an action may be dependent on aprocessor which may interpret the data from the resonance frequencyshift of the split ring resonator, and in response, initiate an action(e.g. a command to take action to modify an environmental condition,etc.). In other embodiments, taking an action may occur without use ofan external processor. For example, an item may be transported whichmust be kept within a predetermined temperature. In order to determine atest the integrity of the temperature while the item is transported, atemperature sensor embedded with split ring resonators may be affixed tothe item, and if the temperature exceeds a predetermined threshold,deformation of the sensor may cause a physical manifestation (change incolor, deformed indicator, etc.). As such, an environmental change ormanifestation may be directly associated with a state of the split ringresonator.

In one embodiment, aviation related applications may include detectionof material stress, temperature or vibration levels approaching orexceeding known tolerances as the aircraft experiences subsonic,transonic, supersonic, and hypersonic speeds. Employing split ringresonators within and over the surface of the wings, includingaileron(s), elevator(s), and rudder(s), may detect air pressure bothabove and below the wing surface, temperature increases and decreases,surface area distortions, and even potential material fractures orfailures, thus providing opportunity to alert both the pilot and groundpersonnel to potential danger to the aircraft and provide adequate timeto respond and correct airspeed, lift, flight posture, payloaddisbursal, and so forth before any catastrophic event may occur.Additionally, applicable embodiments may include fixed wingconstructions conjoined with aero-foil blades within and upon whichsplit ring resonators are used to measure air pressure above and beneaththe aero-foil surface to determine optimal extension or retraction ofsaid aero-foil, thus providing opportunity to adjust flight parametersand maximize aircraft performance. In another embodiment for aviation,employing split ring resonators within and over the surface of thewings, including aileron(s), elevator(s), and rudder(s), may detect atwhat point the harmonics or geometry of the wing surface begin to deformand turn smooth air into turbulent.

In yet another embodiment, aviation related applications may includeaircraft jet engine turbo fan and propeller engine fault tolerancemeasurements and the potential dangers of exceeding those tolerances.For example, split ring resonators may be employed in virtually everyengine part, including housings and cowlings, to provide temperatureshift, vibration frequency increases and decreases, material flex ordistortion, air intake, fuel intake, combustion, manifold pressure, oilpressure, compression, and/or exhaust measurements. By way of example,split ring resonators on the surface area of an engine's propeller maydetect and provide indication of ordinary measurements like speed ofangular rotation, axial and/or centrifugal airflow, and torque, and morepotentials threat-analytical measurements like undue stress or flexexperienced by propeller and fan blades, microscopic stress fracturesdeveloping in the same, excessive temperature, engine lubricantviscosity breakdown rate and degree, and so forth, thus alerting pilotsto potentially immediate need of corrective action to prevent imminentor eventual engine failure and enabling maintenance personnel todetermine possibly appropriate remediation measures to undertake inmaintenance cycles.

In still another embodiment, aviation related applications may includeboth fixed and separable (modular) fuselage integrity measurementparameters and changes thereto from inside and outside forces duringflight and on the ground. Split ring resonators may be used within andon the surface of the fuselage to detect varying levels of distortionfrom internal and external air pressure, temperature shifts, vibrationfrequency increases and decreases experienced during take-off (orlaunch), increases and decreases in altitude, and/or increases anddecreases in airspeed, and provide early warnings of possible structuralfailures in the metals and/or composites associated therewith before acatastrophic event may occur.

In one embodiment, biomedical related applications may include detectingslight alterations and/or undue wear in components in a patient'sprosthetic limb(s). Through the use of split ring resonators, small(even microscopic) changes in the composition and/or shape of aprosthesis component may be detected and addressed very early, perhapseven before any pain or discomfort manifests itself to the patient. Forexample, a fixed-bearing or mobile-bearing knee prosthesis used in kneereplacement surgery may develop slight misalignment or contortion as aresult of stress from weight-bearing and/or other environmental effectsresulting in possible pain or discomfort experienced by the recipient.More specifically, employing split ring resonators in conjunction withthe contact surfaces of a femoral and/or tibial component of aprosthetic knee may reveal slight differentiations in pressure and/orstress points as well as possible degradation of the polyethylenearticulating surfaces associated therewith, thus alerting medical staffto a potential need for adjustment, maintenance, and/or outrightretrofit to maximize comfort and stability for the patient.

In another embodiment, biomedical related applications may includedetecting possible shifts in the position, flow, and/or range of motionwith regard to any one of dozens or hundreds of medical implants in apost-operative setting. In one example, one or more split ringresonators may be utilized to ensure that an artificial heart valveimplant does not move or shift position during operation and/or does notseize up and possibly restrict the free flow of non-oxygenated oroxygenated blood to or from the heart itself, thus risking significantinjury or fatal consequences for the patient. If placed on or withinboth the valve implant and the arterial wall adjacent thereto, splitring resonators may alert the patient and/or medical personnel to minoror major aberrations requiring adjustment or refitting to restore properheart valve function, possibly even before the patient experiences anyovert symptoms at all.

In yet another embodiment, biomedical related applications may includedetecting the effectiveness or need to adjust orthotics designed toimprove, restrict, attenuate and/or brace or bolster patents' range ofmotion and comfort. The use of split ring resonators with regard to theapplication of orthotics may assist in helping correct or counterbalanceloss or impairment of a patients' otherwise normal gait affected bysignificant neurological dysfunction and/or injury or trauma. In onesuch example, split ring resonators installed within and upon carbonfiber and/or other composite ankle and/or foot orthosis, with acounterpart knee orthosis featuring an extension swing assist mechanism,may detect stress, pressure, and/or range of motion outside ofacceptable parameter values, thus indicating that further adjustment isrequired to achieve the desired level of foot drop correction, kneesupport, improved balance, enhanced proprioception, and improved gaitbiomechanics for the patient.

In still another embodiment, personal protective equipment (PPE) relatedapplications may include improving effectiveness of said PPEs to detectcertain compounds and/or viral strains within moisture droplets thatcome into contact with the material of, for example, a face mask. By wayof specific example, because split ring resonators based on carbonaceousgrowth can be tuned serve a specific detection-related purpose, suchsplit ring resonators may be infused within the fibrous materials of anN-95-type face mask (or any type of face mask) with a variety ofdifferently-tuned split ring resonators capable of detecting specifictypes of molecular compounds and/or viral stains, thus enabling thewearer, and (particularly) medical personnel, to quickly determinewhether a risk of contagion and/or imminent illness might be animmediate threat and engage appropriate quarantine, treatment, orremedial protocols to minimize negative effects.

For example, in one embodiment, the face mask may be used to detect aspecific strain (such as COVID), and when the specific strain isdetected, the face mask (or a specific portion of it) may visibly changea color, at least in part. Such may be indicative that the user of themask has contracted the specific strain. Additionally, other virussensors may be installed in any location (e.g. bus entryway, metro car,subway entrance, etc.) such that based on ambient air passing by, if thespecific strain is detected, it may change colors, indicative that anindividual has passed by that sensor who has the specific strain.

Further applicability of use of split ring resonators for detectingbiomaterials may be found in U.S. patent application Ser. No.17/382,661, entitled “METHOD OF MANUFACTURING A GRAPHENE-BASEDBIOLOGICAL FIELD-EFFECT TRANSISTOR,” filed Jul. 22, 2021, the contentsof which is herein incorporated by reference for all purposes.

Within the context of airport security, such sensors could be embeddedwithin typical metal detection systems such that when an individual isbeing scanned, the air being expelled from the individual may beanalyzed to determine the presence of the specific strain. In onecontext, a low-cost fabric-based sensor could be hung within the metaldetector such that when an individual passes by the air may beautomatically analyzed, and a color change may occur on the low-costfabric if the specific strain is detected. Such detection may occur evenwithout requiring electronic configuration or parts. Alternatively, thesensor may be electronically attached to a processor such that when theair is analyzed, if the specific strain is detected, a response (e.g.alarm, notification, etc.) may occur.

In one embodiment, utilities related applications may include detectingslowly and/or suddenly developing faults in high-power line conductorstructures and/or housing/insulating sleeves. As an example, split ringresonators may detect stress flexing or fractures in protective powerline insulation and/or housing sleeves that could possibly become acontributing factor in allowing sparks or other direct effects topotentially impact or ignite wildfires due to a relative proximity ofdry vegetation (e.g., grasses, trees, leaves, etc.) to power linestructures. More specifically, the use of split ring resonatorsinstalled within and around one or more layers of housings and/orsleeves installed radially around the master conductor cable may detectthe development of small (even microscopic) faults over time that, ifleft unchecked, might leave the master conductor wire(s) dangerouslyexposed to natural elements.

In another embodiment, utilities related applications may includemeasuring liquid and/or gas flow through one or more forms of deliveryapparatus (pipelines) and measure any changes in the shape, temperature,structural integrity, and stress (due to internal and/or externalpressures) possibly affecting performance of said delivery system. Inparticular, split ring resonators may be employed to help maintainoptimal operational pressure levels in delivery pipelines by detectingand alerting operation and maintenance personnel to changes in thecomposition of the delivery mechanisms' physical structure (cylindricaland otherwise) and possibly detect even microscopic faults in structurematerial that, if diagnosed and handled at an early state, will notmature and manifest into catastrophic loss or damage to the pipelinedelivery system as a whole. By way of a different example, split ringresonators may detect over-pressurized delivery segments, thus allowingoperation and maintenance personnel the opportunity to make upstreamand/or downstream adjustments to keep such pressure within standardoperational thresholds and alleviate undue stress leading to additionalmaintenance, repair, and/or even replacement.

In one embodiment, construction related applications may include the useof split ring resonators to detect stress, unforeseen or uncalculatedload-bearing, and/or other environmentally-based effects on performance,including but not limited to ambient temperature changes, moistureindices and/or saturation, and relative physical size of the rawmaterials employed to provide requisite support, load balancing, andstability. By way of example, split ring resonators positioned along thelong axis of a support beam and/or joist in the rafters of a rooftopconstruction may reveal unforeseen flexing of said beams or joists, thusalerting the builder and/or occupant to potentially hazardous conditionsof flex stemming from the method of construction relative to weigh borneby said construction. In addition, where structural materials other thannatural wood are employed (including but not limited to composite steel,plywood, or oriented strand board, etc.) split ring resonators embeddedwithin the structure of the load-bearing material itself may detectsmall imperfections or faults developing over time that could eventuallylead to failure of the support structure should fault severity riseabove a predetermined threshold.

In another embodiment, construction related applications may includedetecting changes in the composition and structure of extremelyhigh-level load-bearing steel-reinforced or purely concrete supportpylons for pedestrian as well as vehicular bridges, elevated railways,parking structures, multi-level housing and commercial structures, etc.More specifically, split ring resonators integrated as part of thecomposite material of a reinforced concrete pylon structure, as well assurface-installed split ring resonators capable of detecting changes incomposition, may be employed to detect the initial development of smalldefects, and/or presence of existing slight defects following casting,that could possibly require further external support and/or otherremediation measures necessary to preserve the integrity of thestructure and continue providing adequate load-bearing according to thedesign thereof.

In still another embodiment, construction related applications mayinclude ensuring adherence to fire-prevention and other safety measuresrequired by governmental standards and regulations. In such a capacity,split ring resonators may help detect the unlikely occurrence of, forexample, unforeseen and unnoticeable alterations in constructed“firewalls” and/or other fire-resistant assembly systems comprisingmetal frames and lightweight structural cementitious (SCP) panels.Specifically, split ring resonators may detect small “gaps” developingin the installation of the firewalls or SCPs and alert builders and/ormaintenance personnel to those protective measures having fallen out ofcompliance with the aforementioned governmental regulations whereotherwise casual visual affirmation measures may not detect saidnon-compliance.

In one embodiment, nautical related applications may include detectingany changes in the structural integrity and/or wind pressure applied tothe sailcloth of an unfurled sail as the draft of the sail opens upunder wind loading. Employing split ring resonators on the surface of,and/or in between multiple cloth layers comprising, a sail may providecritical real-time information to the sailing crew of a potentialproblem with the integrity of the sail when in use. In one specificexample, split ring resonators may be able to detect materialdistortions or faults within and upon a spinnaker sail composition underthe stresses associated with wind loading during casual and/orcompetitive sailing, thus enabling the crew to more quickly affectnecessary adjustments to the spinnaker sail posture with regard to itstethering to the mast, spar, and/or stay.

In another embodiment, nautical related applications may includedetecting changes in solid and/or tubular mast compression when a mainsail (or main sheet) experiences varying degrees of wind loading duringnormal operation. By way of example, the use of split ring resonatorsaffixed to the surface of a bendable/flexible mast may assist thesailing crew in determining whether the optimal level of wind loadapplied to the main sail is being achieved and/or whether an adjustmenttherefore is required. Additionally, the use of split ring resonatorsaffixed to a rigid mast construction may detect degrees ofundue/unplanned flexing of the mast during operation, possiblyindicating an excess of wind loading force upon the main sail that thecrew may diagnose and make appropriate adjustments to return to optimalperformance. Further, the use of split ring resonators employed bothwithin and attached to the exterior of sold and/or tubular masts may aidthe crew in detecting early signs of stress faults developing in themast's material construction, thus enabling the crew to more accuratelydetermine a window for more comprehensive testing, maintenance, and evenoutright replacement where fatigue has passed beyond a predetermined“safe” threshold.

In yet another embodiment, nautical related applications may includedetecting changes and/or aberrations in the construction of vesselcomponents (particularly the hull) due to outside forces liketemperature (both in and out of the water), small and large strainspossibly affecting metal, composite, and/or alloy material constructionperformance when both anchored as well as under propulsion. By way ofone example, the use of split ring resonators may detect changes ordistortions of the pontoons of a catamaran, for instance, when sailingover calm and/or challenging waters. Specifically, where multi-hulldesigned watercraft are generally employed due to superior ability totravel at higher speeds and remain relatively more stable than theirmonohull counterparts, part of that comparison equation between the twomay involve hull surface areas in contact with the water duringoperation. Employing split ring resonators on the surface of the hull(s)of such a watercraft may detect temporary changes, aberrations, and/ordistortions in the shape of the hull(s) due to changes in watertemperature, impact of wake, material flex during in operation, etc.that might lead to increased drag potentially translating to a lowerachievable speed than when optimal hull surface shape is maintained.With that information, watercraft crews may have the ability to possiblyadjust one or more environmental parameters in an effort to return tooptimal performance. In one embodiment, such environmental parameters(e.g. angle of sail, length of cord, etc.) may occur automatically(based on an actuator attached to a process to process the data from thesplit ring resonator(s)).

In one embodiment, forging related applications may include detectingminor aberrations in the consistency/density of forged metals,composites, and/or alloys. The arena of forging metals, composites,and/or alloys may span two major stages of implement production:applying high levels of heat and casting of ingot blanks, and the actualshaping and creation of the end-result implement derived from the forgedmaterials. The first example may involve using split ring resonators tohelp detect very small (even microscopic) deformities and/or aberrationsin the raw metal, composite, and/or alloy that could potentially affectthe quality, strength, and reliability of the finished productexemplified by the second example. The second example, the end productof the forging process, may benefit from split ring resonators bothwithin the metal, composite, and/or alloy raw material as well asaffixed to the exterior of the finished product because the resonatorsmay help detect surface shape, density, and/or consistency variationsoutside of acceptable established parameters. By way of a specificexample, employing split ring resonators in the forging of the shaftand/or head of a golf club (an “iron,” for example) may alert themanufacturer and designer to a slightly inaccurate club head angle orpossibly weaker-than-expected coupling between the golf club shaft andhead when assembled, or the split ring resonators may detect a club headshape that is slightly inconsistent with the strict design guidelines,thus requiring a reforging or other material adjustment to bring theclub back into compliance with manufacturing standards.

In one embodiment, power production related applications may includeestablishing and maintaining consistency and optimal performance ofindividual solar cells within a large solar panel array. For example,split ring resonators may be integrated into the actual material ofindividual solar cells when fabricated which can detect when thematerial of the cell may be degrading or performing outside ofestablished norms during regular operation/collection and retentionperiods. Additionally, split ring resonators may be employed adjacent tothe array of solar cells (between the cells and the encapsulant, forexample) to detect whether the solar array as a whole is experiencingcompromised performance, or merely one or more individual cells.

In another embodiment, power production related applications may includedetection of environmental conditions related to the structure andoperation of a hydroelectric dam and/or the power plant(s) associatedtherewith. Using split ring resonators within the construction of a dammay provide the ability to detect changes in the composition of damconstruction materials (including, but not limited to, components suchas antiseepage armored concrete, concrete stake, first sealing metallicplate, metal connecting plate, second sealing metallic plate, and secondantiseepage armored concrete) and enable builders, operations personnel,and maintenance personnel to analyze real-time data about the currentstate of the dam's structure, perhaps providing early warnings ofpotential faults that, left unaddressed, may mature into full-fledgedcatastrophic breaches in the dam's primary function. Specifically,constructing the dam with split ring resonators installed within the rawcement pours that constitute the dam's primary structure may enablesensors installed in and around the dam to provide early warning ofslight changes, distortions, and or deformities in the anti-seepagearmored concrete structure(s), thus enabling the operation andmaintenance personnel an opportunity to remediate or mitigate anypotential issues before any real problems surface.

In yet another embodiment, power production related applications mayinclude constantly monitoring and assessing the viability and conditionof horizontal-axis wind turbine stands, blades, and/or energygenerators. The use of split ring resonators may detect changes in fanblade durability, wear, and posture, shape, strength, and durability ofvertical stands, and/or standard operation of the turbine itself. By wayof specific example, placement of split ring resonators on both theblades of a horizontal-axis wind turbine apparatus, as well as the hubto which those blades are attached, may provide early indications thatan individual blade's (which may consist, in one embodiment, ofaluminum-fiberglass hybrid construction) connection to the hub isweakening over time, thus requiring possible maintenance and evenreplacement, barring appropriate remedial measures. Early detection ofthese types of possible faults saves time and money in that “an ounce ofprevention may be worth a pound of cure,” and maximized operation timemay be directly related to sustained, or even increased electric energyproduction.

In still another embodiment, power production related applications mayinclude detecting and tracking changes in natural gas storage andtransport conduits. As one of the costliest, (in terms of time, capitalexpenditure, potential energy loss, and additional maintenance cycles)issues with natural gas storage and transfer, leakage along any of thewide range of physical systems involved in delivering natural gas energysources is a problem that may be minimized or alleviated altogether withthe use of split ring resonators deployed throughout the system. By wayof example, split ring resonators applied to the physical deliveryconduit(s) that transport natural gas from point A to point B can detectpotential leaks early by providing indications to operations andmaintenance personnel that potential faults, distortions, and/oraberrations are forming within the material of the transport conduit(s)directly and/or any joints or junctions where a piece of transportconduit may be physically attached to one or more additional components.Additionally, being able to detect leakage of a predetermined gas (e.g.methane, etc.) may have green applicability in that environmentallyharmful gases may be detected and stopped before causing significantdamage.

In one embodiment, manufacturing related applications may includedisplaying information about component amalgamation and/or finalassembly status (conforming or non-confirming) of a given product at theend of the build and assembly process. Employing split ring resonatorsin precise locations on individual parts brought together to form acomplete machine or other product can detect if and where possibleinaccuracies and/or misalignment may be present in the final assembly.For example, if three parts A, B, and C of an end product are to beassembled according to known strict tolerance guidelines with regard tospacing and/or alignment, split ring resonators positioned so as todetect the presence (or absence) of other precisely placed split ringresonators—for the purpose of affirming whether the two pieces A and B(or B and C, or A and C, as the case may be) are correctly connected toone another without undue variance in specified gaps or alignment—maydetect where an assembly fault may be present based on proximitymeasurements between the split ring resonators falling outside ofacceptable tolerances.

In another embodiment, manufacturing related applications may includedetecting any potential faults or errors within an apparatus by way ofpost-production testing. The use of split ring resonators affixed tocrucial locations of a newly-manufactures supersonic-capable jet engineafterburner assembly may provide critical information to the engineersand maintenance personnel regarding the accuracy of said assembly whenperforming its function in otherwise real-world conditions.Specifically, affixing split ring resonators to thelongitudinally-movable shroud and variable area exit nozzle comprisingthe afterburner “thrust-shaping” mechanism can provide vital informationregarding that assemblies post-production performance by relayingwhether said shroud and nozzle functions are performing withinestablished optimal tolerances, thus ensuring proper functionality priorto ultimately introducing said afterburner assembly to the supersonicjet fighter on which the assembly will perform its intended function.

In one embodiment, agriculture related applications may includedetecting and tracking growth rates among a sample of agriculturalproducts to determine whether those specimens are growing at rateswithin established guidelines (e.g., not growing too slowly, but alsonot growing too fast). Because it would be difficult, and perhapsunreasonable, to place split ring resonators within the actual fiber ofplant specimens, themselves, split ring resonators employed on keyexternal points of the non-edible portion(s) of such agriculturalspecimens may detect growth rates when pinged at the correct intervalsover the span of a typical growth cycle of said plant specimen. Inaddition, split ring resonators employed may be used to simply detectand report on surface temperature readings over the course of a setpolling period by reporting the surface temperature back to the pollingmechanism each time a ping is conducted thereon, thus allowing thegrowers and botanists information relevant to the temperature of givenagricultural specimens over the course of a growth cycle period.Further, split ring resonators may be employed to also provide keyinformation about moisture saturation of agricultural specimens to whichthe split ring resonators are affixed. That is, whenever the polling andrecording mechanism seeks a response form the one or more split ringresonators affixed to a given group of agricultural specimens, personnelmonitoring the growth process may be able to discover whether, and byhow much, the moisture saturation of one or more agricultural specimensdemonstrates a measurement outside (either too little or too much) ofacceptable parameters and possibly learn something about the effects ofsaid moisture aberrations. Further still, split ring resonators may beable to detect whether, and by how much, agricultural specimens may beexposed to inadequate, inadequate, or excessive ultraviolet light duringa growth cycle. When affixed to key external points of the non-edibleportion(s) of such agricultural specimens, split ring resonators affixedto plants both within and out from under shaded areas may closely trackeach specimen's exposure to direct, indirect, or obscured light sourcesby way of readings returned during regular polling by polling andrecording mechanisms.

In one embodiment, space travel related applications may includedetermining whether spacecraft modules are fitting together and asdesigned and remain safe for astronauts as well as other sensitivebeings and/or inanimate payload on the ship. By way of one specificexample, split ring resonators may be employed in conjunction with twospacecraft vehicles and/or spacecraft modules which are at some pointconnected or conjoined while operating in a zero-gravity setting. Thesplit ring resonators may detect whether the conjoining processes (wherecontrollers are designed to articulate the coupling system in order forthe active half of the coupling system to successfully capture thetarget component, align the two, and establish an otherwise static/rigidconnection) are completed accurately and safely by alerting astronautsand/or other monitoring personnel to potentially hazardous conditionsbased on proximity, air pressure, temperature reading tolerances are orare not within acceptable guidelines.

In another embodiment, space travel related applications may includeconstant solid rocket propellant integrity monitoring and reporting forall launch stages (before, during, and after) of a space vehicle. Forexample, solid rocket propellant (SRB) composites must remaincrack/defect-free, as propellant composites which contain cracks presenta risk of explosive failure of the vehicle. If not properly monitoredfor potential faults/cracks/defects, solid propellant systems may beinadvertently ignited by multiple possible causes including mechanicalshock and static electricity. The possibility of employing split ringresonators in both the actual composite fuel mix, as well as upon thesurface of the solid fuel element, can provide a detection medium forastronauts and ground crew to receive early warning of possible faultsin an SRB fuel source before launch of the vehicle and subsequentpotentially devastating failure.

In another embodiment, space travel related applications may includedetecting and tracking the effects of external forces on the framing,body, and components of a rocket-propelled vessel during launch. Extremeheat, vibration, air pressure increases and decreases, and/or torqueintroduced by lift-off are just a few of the outside forces that mayhave potentially negative impact on the launch vehicle during actuallaunch. Such forces may lead to changes and/or distortions in thesurface shape of the launch vehicle which could impose potentiallydangerous results if not detected early and mitigated effectively. Thus,employing split ring resonators over the surface and within thecomponents of a launch vehicle may help provide real-time data aboutchanges in conditions and/or other unexpected circumstances to theastronauts and ground personnel who can then affect minor ad hocadjustments in telemetry, etc. to keep the launch process progressingaccording to design parameters.

In one embodiment, professional sports equipment related applicationsmay include monitoring and tracking raw data from a professionalathlete's protective (and non-protective) equipment during competition.One high-profile example involves the use of a football helmet inprofessional football contests (as well as other sports requiring helmetuse) and the necessity for that helmet to provide adequate protection tothe wearer against concussion (or worse) brought on when the wearer'shead experiences both linear acceleration and rotational accelerationdue to a variety of impact types over the course of a contest. By way ofa specific example, split ring resonators may be installed in the crownenergy attenuation assembly (or “padding”) formed from absorbent foam,air, gel, or a combination thereof and integrated into the constructionof a player's helmet. In fact, split ring resonators may be a part ofthe actual material composition (of the absorbent foam, for example) inthe helmet and used to detect extreme compression within one or morespecific pressure points within the helmet during impact. Thus, athletictraining staff on the sideline of a contest in progress may conceivablyreceive real-time “alerts” that one or more absorbent foam insertswithin a particular player's helmet have just received a potentiallyexcessive (dangerous) impact without the player, themselves, evenneeding to alert said personnel to the potential issue as all.

In one embodiment, professional sports equipment related applicationsmay include monitoring the integrity of other perhaps lessersafety-oriented equipment required for success in a particular player'sgiven competition. By way of specific example, professional hockeyplayers may be prevented from playing (in the course of normalcompetition) without a suitable hockey stick used to manipulate the puckaround the ice during competition. If and when a stick breaks, thatplayer may be required to immediately discard the broken implement(which nearly always culminates in the player dropping the remnants ofthe broken stick in question wherever they happen to be on the ice atthat moment), thus rendering the player essentially ineffective for anytime he/she is on the ice during competition. Using split ringresonators both within the construct and on the outside of graphitehockey sticks (and attached to the exterior of a natural wood hockeystick) would enable bench personnel to learn whether the integrity of ahockey stick in use may be approaching a breaking point before thatstick actually breaks, thus allowing the player to switch to a brand newstick before any such failure. In addition, another hockey-orientedapplication may involve snap-on-snap-off replaceable skate blades. If areplaceable skate blade were to unexpectedly release and/or becomedetached from its housing during competition, the results could befatal. The use of split ring resonators on the two conjoining elementsthat constitute a replaceable skate blade connection may detect whethera separation is imminent based on a change of proximity of the two splitring resonators, thus allowing the player and/or bench staff to affect anecessary adjustment and/or reconnection in order to prevent such aseparation during competition.

In one embodiment, lubricant (and other vital fluids including but notlimited to fuel, coolants, and other process fluids) viscosity and/ormolecular degradation related applications may include detecting, at amolecular level, when a vital fluid (such as motor oil) begins to breakdown within an engine during operation. By way of one specific example,microscopic split ring resonators infused within the actual compositionof the liquid may detect molecular degradation of the fluid over thecourse of regular engine operation by, for example, detecting increasedlevels of foreign matter within the liquid (e.g., carbon deposits fromthe many thousands of ignition chamber combustion events, etc.), thusenabling an outside monitoring component the ability to display a reportor initiate an alarm to alert operations and maintenance personnel whena potential threshold level of foreign particulates have become “partof” the lubricant pool within the engine requiring flushing andrefreshing of lubricant to prolong the life of the machine in question.It should be noted that similar split ring resonator use may beapplicable to the known other aforementioned engine-operation liquidsincluding fuel, coolant, and process fluids like hydraulic fluid, etc.

In one embodiment, rechargeable battery composition, charging, andrecharging related applications may include detecting when and howsevere changing conditions within the membrane components (cathodes,anodes, separators, etc.) of a rechargeable battery may be in real time.For example, electrodes attached to the external casing of arechargeable battery may receive detection information from split ringresonators integrated throughout the cathode (and/or anode) of a lithiumbattery during the initial charging, discharge, and recharging phases ofbattery operation. Detection of anomalies or inconsistencies in thematerial make-up of the cathode (and/or anode) membranes by the splitring resonators may, thus, alert operations personnel to a potentialproblem with a single cell, or even a block of lithium cells, in alarger battery housing which could potentially affect overallperformance.

Additionally, in some embodiments, pinging the split ring resonators mayoccur by an external source (such as a ping to a split ring resonatorlocated on a surface of a vehicle). In other instances, pinging thesplit ring resonators may be prevented by a surrounding impediment (suchas when the split ring resonators are embedded in a liquid, or within asteel structure such as an engine, etc.). In those instances, data maybe collected where the split ring resonators are located. For example,if split ring resonators are within a liquid traveling through anapparatus, such split ring resonators may be pinged during the course oftravel by a microprocessor (located also within the liquid) and data maybe recorded during the course of travel. In this manner, when the liquidexits the apparatus, data collected during the course of travel may beprovided. Further, such data may be correlated with signatures andconditions associated with the apparatus in which it was traveling. Forexample, if split ring resonators are embedded within a lubricant, suchlubricant may be sent through an engine, and after exiting, dataassociated with the split ring resonators as it traveled through theengine may have a timestamp associated with each ping such that aparticular location of the split ring resonator may be correlated withthe timestamp. In this manner, an aberration detected internally may beascertained after the lubricant has exited the apparatus. Additionally,in another embodiment, data obtained from pinging the split ringresonators may be received internally (within the system in which thesplit ring resonators are embedded) and communicated via a hard wiredconnection to an external antenna which, in turn, may communicate thedata to an external data collecting source.

With respect to fleet management, split ring resonators may be used in avariety of contexts. For example, maintaining a fleet (e.g. drone,vehicles, trucks, planes, etc.) in good working condition may be basedon individual readings of split ring resonators in each item. Knowingwhen an item needs to be taken from use and serviced is often basedon 1) predetermined time or travel thresholds; or 2) device failure(indicative that it needs to be repaired). Having split ring resonatorsembedded within such fleet item would allow for precise management of afleet such that an item is serviced whenever a sensor on the itemdetects a change in state 3) with respect to fleet management,individual vehicle or part wear and failure data can be communicatedinto the fleet's and part manufacture's warehouse and factory ordersystem (CRM) to better synchronize just in time parts in advance of ascheduled service to improve more accurate forecasting of needed partsat the manufacturing site or warehouse site. Additionally, massmanagement (service warehouse, real estate houses, commercialproperties, etc.) can be time and cost intensive to maintain. Split ringresonators can be tuned for specific sensitivities (such as detectingwhen a layer of dust is found on a floor). Such an applicability couldapply even to research facilities (which operate in no dust zones).

In various embodiments, operation of the split ring resonators may beused for triangulation (or location positioning). Additionally, aresponse from a split ring resonator may, in turn, cause a response in asecond split ring resonator, which may, in turn, generate anotherresponse in a third split ring resonator, and so on and so forth. Inthis manner, a response from a single split ring resonator may besequenced through other split ring resonators as needed. In anotherembodiment, operation of the split ring resonators may be used fortriangulation (or location positioning) in areas where GPS data isnonexistent, compromised or insufficiently accurate for precisenavigation and location.

In another embodiment, the mattress industry may use split ringresonators to modify the contours of a mattress to match a preference ofa user. For example, a user may want to decrease pressure at a certainpoint of the mattress (to alleviate back pain, etc.). As a user lies onthe mattress, the split ring resonators (which may be embedded withinthe mattress, within a foam material, etc.) may indicate pressure pointsacross the entire mattress. A processor associated with the mattress maybe used to interpret such data and modify the contours of the mattress(including by mechanical manipulation, expansion/retraction of foam inthe amount of compression, etc.) to achieve the desired outcome (aspecific pressure at the specific point indicated). Additionally, adoctor may provide a specific set of mattress pressure points (toalleviate a condition) which may be inputted into the mattress such thatwhen a user lies on the mattress, the mattress may be configured in realtime to meet the prescribed pressure points. Further, as a user changesposition in bed (from side to back sleeping, etc.), the mattress maycontinually adjust the contours of the bed to meet the predeterminedpressure points, regardless of the position taken by the user.

Still yet, in one embodiment, the split ring resonators could be used todetect a growth on an object. For example, the split ring resonators maybe embedded into fiber and composite fiber such that if black mold grew,for example, on the surface of wall (such as an inside wall that is notoutwardly facing), the black mold may be detected on the surface of thewall. Additionally, the split ring resonators may be used to detect aleak (such as a water leak in a basement of a house). Thus, within thecontext of house maintenance and safety, split ring resonators may beused to detect the state of the house.

Further, split ring resonators may be used to detect integrity ofmedication (such as medication spoilage). Additionally, it may be usedin a sensor to detect a physical condition (presence of gangrene, bloodsugar levels for diabetes, etc.).

FIGS. 50A and 50B show sensors 5000 and 5100 integrated into anadhesive, in accordance with one embodiment. As an option, the sensors5000 and 5100 may be implemented in the context of any one or more ofthe embodiments set forth in any previous and/or subsequent figure(s)and/or description thereof. Of course, however, the sensors 5000 and5100 may be implemented in the context of any desired environment.Further, the aforementioned definitions may equally apply to thedescription below.

As shown, an adhesive 5002 may include one or more split ring resonators5004. Additionally, the split ring resonators 5004 may respond to aninterrogation signal 5006.

In various embodiment, the split ring resonators 5004 may be printedand/or disposed on or in the adhesive 5002. For example, the split ringresonators 5004 may be formed from a carbon-containing material, and theadhesive 5002 may be a non-elastomeric material or a semi-rigidmaterial. Further, the adhesive 5002 may include a porous flexiblematrix. The split ring resonators 5004 may be tuned for high sensitivityby using chemically reactive materials in the porous flexible matrix.Additionally, it is to be appreciated that sensitivity parameters (ofthe split ring resonators) can be optimized for a variety of particularapplications (as disclosed and described herein). Further, the splitring resonators 5004 may be printed and/or disposed on or in a stick andpeel assembly. Thus, the stick and peel assembly (e.g. a sticker) may beconfigured to include split ring resonators 5004. In one embodiment, thestick and peel assembly may include placing the sticker onto a desiredsurface, and then removing a protective film to activate sensing.

In various embodiments, sensing by the split ring resonators 5004 may beduring exposure such as while in motion (as affixed to a moving object).Additionally, sensing may be measured after exposure (e.g. from astationary object/location, etc.). Further, the split ring resonators5004 may be exposed to chemistries of volatile substances, which inturn, may affect the permittivity of the split ring resonators 5004embedded in or on the adhesive 5002 (e.g. sticker). The permittivity, inone embodiment, may store detected concentration levels of volatilesubstances.

Further, the split ring resonators 5004 may be interrogated via theinterrogation signal 5006 such that a permittivity of the adhesive 5002may be collected. In various embodiments, the permittivity may include achange of permittivity over a time period. It is to be appreciated thatthe interrogation signal 5006 may include an active and/or passiveinterrogation, and/or be configured as needed depending on the needs ofthe application of the adhesive material.

Further applicability of use of resonant frequency shifts of split ringresonators may apply within the context of U.S. patent application Ser.No. 17/884,735, entitled “BATTERY SAFETY SYSTEM FOR DETECTING ANALYTES,”filed Aug. 10, 2022, and U.S. patent application Ser. No. 17/182,006,entitled “ANALYTE SENSING DEVICE,” filed Feb. 22, 2021, the contents ofall of which are herein incorporated by reference for all purposes.

Further, split ring resonators may be used to detect can be placed onindividual containers of consumer packaged goods, e.g. laundrydetergent, milk, etc or consumer RX containers to determine the amountof product remaining in the container and then relay that informationinto a patient's medical management system or automatic re-orderingsystem.

In the foregoing specification, the disclosure has been described withreference to specific implementations thereof. It will however beevident that various modifications and changes may be made theretowithout departing from the broader spirit and scope of the disclosure.For example, the above-described process flows are described withreference to an ordering of process actions. However, the ordering ofmany of the described process actions may be changed without affectingthe scope or operation of the disclosure. The specification and drawingsare to be regarded in an illustrative sense rather than in a restrictivesense.

What is claimed is:
 1. An apparatus, comprising: an adhesive material; and at least one split-ring resonator (SRR) disposed on or in the adhesive material, wherein the at least one SRR is formed from a carbon-containing material, and wherein the adhesive material is a non-elastomeric material or a semi-rigid material.
 2. The apparatus of claim 1, wherein the at least one SRR is configured to have a resonance frequency shift in response to an alteration of the adhesive material.
 3. The apparatus of claim 2, wherein the alteration includes a change in concentration of one or more volatile substances proximate to the at least one SRR or the adhesive material.
 4. The apparatus of claim 1, wherein the adhesive material is a porous flexible matrix.
 5. The apparatus of claim 4, wherein the porous flexible matrix comprises chemically reactive materials.
 6. The apparatus of claim 1, wherein the at least one SRR is configured to resonate at a first frequency in response to an interrogation signal.
 7. The apparatus of claim 6, wherein the first frequency is correlated with a first concentration of a first volatile substance.
 8. The apparatus of claim 7, wherein the first concentration of the first volatile substance is correlated with a first permittivity, and a second concentration of the first volatile substance is correlated with a second permittivity.
 9. The apparatus of claim 7, wherein the first concentration of the first volatile substance is located proximate to an exterior surface of the adhesive material.
 10. The apparatus of claim 6, wherein the carbon-containing material includes at least one of: a carbonaceous growth, three-dimensional (3D) monolithic carbonaceous growth, or a carbon composite;
 11. The apparatus of claim 1, wherein the first frequency is based at least in part on one or more physical characteristics of the adhesive material.
 12. The apparatus of claim 1, wherein the adhesive material in combination with the at least one SRR creates an ensemble frequency effect, based on a combination of a resonance frequency shift of the at least one SRR and a frequency response of the adhesive material.
 13. The apparatus of claim 12, wherein the resonance frequency shift is at a first frequency in response to an electromagnetic ping when the adhesive material is in a first state, and is at a second frequency in response to the electromagnetic ping when the adhesive material is in a second state.
 14. The apparatus of claim 12, wherein a first frequency of the resonance frequency shift indicates a first condition of the adhesive material by generating a first electromagnetic return signal in response to an electromagnetic ping, and a second frequency of the resonance frequency shift indicates a second condition of the adhesive material by generating a second electromagnetic return signal in response to the electromagnetic ping.
 15. The apparatus of claim 14, wherein the first frequency is different than the second frequency.
 16. The apparatus of claim 1, wherein the at least one SRR includes a resonance portion, wherein the resonance portion is configured to resonate at a first frequency in response to an electromagnetic ping when a state of the adhesive material exceeds a threshold, and is configured to resonate at a second frequency in response to the electromagnetic ping when the state of the adhesive material is beneath the threshold.
 17. The apparatus of claim 1, wherein the carbon-containing material includes a carbonaceous growth, and a resonant frequency of 3D monolithic carbonaceous growth is based at least in part on either or both of a permittivity and a permeability of the adhesive material. 